00:03:41 [[User:Xorol]] https://esolangs.org/w/index.php?diff=87923&oldid=86296 * Xorol * (+210) Added some info 01:26:43 maybe then he'e not automated but manned 02:46:57 [[Grue]] https://esolangs.org/w/index.php?diff=87924&oldid=87912 * PixelatedStarfish * (+28) /* Interpreter */ 02:47:07 -!- Guest65 has joined. 02:47:13 -!- Guest65 has left. 02:48:48 [[Trivial brainfuck substitution]] https://esolangs.org/w/index.php?diff=87925&oldid=83915 * PixelatedStarfish * (-53) /* Syntax */ 03:01:24 hah, few months ago I said "I should made a universal translator between all those brainfuck substitutions" 03:01:36 and someone already made it in that wiki page 03:02:26 oh wait, nope, it's just plain bf interpreter 03:02:55 I imagine a translator could go fetch the wiki pate, 03:03:13 *... page, find the instructions table and replace them automatically 04:10:05 -!- chiselfuse has quit (Remote host closed the connection). 04:10:23 -!- chiselfuse has joined. 04:11:01 -!- src has quit (Ping timeout: 252 seconds). 04:14:57 -!- APic has quit (Read error: Connection reset by peer). 04:15:23 -!- APic has joined. 04:16:07 -!- velik has quit (Ping timeout: 240 seconds). 04:54:57 -!- APic has quit (Read error: Connection reset by peer). 05:00:16 -!- APic has joined. 05:59:57 -!- APic has quit (Read error: Connection reset by peer). 06:00:14 -!- APic has joined. 06:04:45 -!- velik has joined. 06:09:57 -!- APic has quit (Read error: Connection reset by peer). 06:10:15 -!- APic has joined. 06:49:29 nakilon: but nobody uses the substitutions other than brainfuck, Ook!, and the two or three that encode brainfuck with repetitions of one byte 06:52:39 I thought Chromium OS is something good, because there is no way to install anything in it, you only use docker, so it's so safe... 06:53:47 until I launched a container from another container mounting the docker socket in both, and server just stopped responding, disks were spinning like mad and even serial console didn't work 06:54:32 this stupid container overrated container thing 06:55:42 yeah I know that thing that I'm trying to build are not what people are supposed to try to build but I was told it's all so reliable... 06:55:52 *things 07:31:44 -!- ais523 has joined. 08:05:49 ok docker sockets were not a reason of hanging; it hanged again _-- maybe it's what happens to Chromium OS when it's out of RAM or idk, it just dies 08:06:37 -!- hendursa1 has joined. 08:09:27 -!- hendursaga has quit (Ping timeout: 276 seconds). 08:10:48 -!- ais523 has quit (Remote host closed the connection). 08:18:35 -!- velik has quit (Ping timeout: 252 seconds). 08:38:41 looks like the linux thing called "oom killer" kills a process but the system goes insane anyway and does not recover 08:39:13 -!- Sgeo has quit (Read error: Connection reset by peer). 08:43:27 -!- wib_jonas has joined. 08:44:10 -!- imode has quit (Ping timeout: 240 seconds). 08:44:12 does anyone happen to know where I can find human-readable info on how to interpret a robots.txt file? 08:49:00 IIRC it's barely standardized 08:50:07 yeah, https://www.w3.org/TR/html4/appendix/notes.html#h-B.4.1.1 has some info but not muc 08:56:39 -!- velik has joined. 09:01:01 lol I did "echo 2 > /proc/sys/vm/overcommit_memory" like this guy proposed https://serverfault.com/a/142003/67097 and now I can't spawn any process even while it's 500 mb of free ram 09:03:28 and now I can't even revert it because sudo sh -c "echo 1 >..." emits -bash: fork: Cannot allocate memory 09:04:10 nakilon: so use the kill builtin 09:04:17 that is why kill is a builtin command in bash 09:04:24 kill what? 09:05:15 yeah, that's the hard part 09:05:28 $ ps 09:05:28 -bash: fork: Cannot allocate memory 09:05:33 yeah 09:05:40 might be easier to reboot in practice 09:05:43 and this was just before that 09:05:44 $ free -h 09:05:44 total used free shared buff/cache available 09:05:44 Mem: 982Mi 290Mi 382Mi 1.0Mi 308Mi 544Mi 09:07:02 Chromium OS is just broken crap; I guess Google does not care about the scenarios when somethings runs out of memory -- they just stop the machine and spin up a bigger one, and probably expect me to do the same 09:07:11 on every single task 09:08:02 gotta switch to ubuntu 09:17:19 Does bash have a `readlink`-capable builtin? I imagine you could make a poor man's ps out of looking at /proc/pid/exe that way. Hmm, apparently not. 09:18:10 -!- velik has quit (Ping timeout: 240 seconds). 09:21:43 `` for p in /proc/[0-9]*/stat; do read -d'\t' pid prog rest <$p; echo $pid $prog; done 09:21:44 10 (writeback) \ 11 (kcompactd0) \ 12 (crypto) \ 13 (kintegrityd) \ 14 (bioset) \ 15 (kblockd) \ 16 (kworker/0:1) \ 18 (kswapd0) \ 1 (init) \ 2 (kthreadd) \ 3 (ksoftirqd/0) \ 44 (bioset) \ 45 (kworker/0:1H) \ 48 (cat) \ 49 (`) \ 4 (kworker/0:0) \ 50 (`) \ 51 (`) \ 5 (kworker/0:0H) \ 6 (kworker/u2:0) \ 7 (lru-add-drain) \ 8 (kdevtmpfs) \ 9 (oom_reaper) 09:21:55 I feel like that probably maybe needs no processes. 09:23:22 -!- velik has joined. 09:24:52 -!- velik has quit (Remote host closed the connection). 09:26:31 fizzie: I think that will still fork, even if not exec 09:26:33 but I'm not sure 09:42:39 Hmm, well, from https://0x0.st/-wu8.txt I think not. 09:44:53 Interestingly, repeating `readlink /proc/self` on my work laptop increments the resulting number by pretty much exactly 13 for each iteration, which makes me think there's some sort of an extra per-command or per-prompt hook set up somewhere. 09:47:34 -!- ais523 has joined. 09:47:36 fizzie: cat /proc/*/forks gives the number of processes/threads created total on the system since boot, I think 09:47:44 or at least the user-space ones\ 09:48:20 you can use taht to detect if anything has forked, which is useful to iterate through all processes eg. in /proc and be sure that you haven't missed any, eg. to kill all processes by a user 09:48:25 hmm, does that count both fork and clone? there are two ways to create processes nowadays 09:48:31 (I think Linux doesn't have a spawn in kernel-space) 09:48:32 ais523: yes, it counts clone 09:48:39 I checked that once in the kernel source code 09:48:45 of course things may have changed since\ 09:48:51 let me look up the exact name of the file 09:51:20 There's a "processes N" field in /proc/stat at least. 09:54:06 yes, the filename is /proc/stat 09:54:09 So I guess https://0x0.st/-wuT.txt is more direct evidence of not creating new processes. 09:54:13 you were faster than it took me to look it up 09:54:36 (it was among my emails, but was spoilered so a plain text search didn't find it easily) 09:54:48 it's not "forks" 09:55:02 yep 09:55:13 and it's a 64-bit counter, so it can't overflow either 09:56:28 mostly though I think if my computer hangs swapping and can't start a new process, I just reboot it 09:56:28 For some reason PIDs that are >= 2^16 just feel weird. 09:57:01 (possibly reboot with more and more rescue options if it happens right after boot with no chance to interrupt) 09:58:26 fizzie: it feels good, it means we finally managed to shed another piece of historical accident that held us back. there's still a control somewhere in /sys or /proc to limit pids if you don't like it though. 10:14:36 -!- wib_jonas has quit (Quit: Client closed). 10:20:56 -!- wib_jonas has joined. 10:41:24 -!- riv has joined. 10:45:01 -!- APic has quit (Read error: Connection reset by peer). 10:45:20 -!- APic has joined. 10:58:50 -!- tech_exorcist has joined. 11:15:37 -!- wib_jonas has quit (Quit: Client closed). 11:26:51 -!- dyeplexer has joined. 11:29:42 -!- tech_exorcist has quit (Remote host closed the connection). 11:32:01 -!- tech_exorcist has joined. 12:04:23 interesting, 2FA not via SMS but via phone call that you don't need to accept 12:04:33 you just type the last 4 digits of the number 12:04:53 so they own 10000 phone numbers just for that 12:09:37 -!- arseniiv has joined. 12:40:36 maybe they're just spoofing the number? 12:42:35 -!- dyeplexer has quit (Ping timeout: 252 seconds). 12:44:57 -!- dyeplexer has joined. 13:41:59 -!- arseniiv has quit (Ping timeout: 252 seconds). 13:53:19 -!- arseniiv has joined. 14:00:04 -!- Everything has quit (Ping timeout: 252 seconds). 14:02:02 -!- Everything has joined. 14:40:30 "DPI SET to 67 x 34 (wanted 96 x 96)" is what I get when attaching to an xpra session, wonder what's up with that. 14:41:51 Tried to do `--dpi=96` on both `xpra start` on the remote side and `xpra attach` on the local side, but still. 14:55:09 -!- riv has quit (Quit: Leaving). 15:01:14 -!- wib_jonas has joined. 15:01:39 nakilon: well duh, it's easy to own a lot of phone numbers if you release a popular app that people will install on their smartphones 15:02:02 especially since many of those people will have their phones always on and will install just about anything 15:02:27 -!- riv has joined. 15:03:29 of course any other app on the same smartphone that has access to your call logs could spoof that part of the authentication as well 15:03:42 -!- src has joined. 15:04:05 -!- riv has quit (Client Quit). 15:05:15 it doesn't even have to be that same app, it could be another app that's a game with shiny colored balls and fewer ads than usual that they control that gives them the phone numbers 15:05:20 -!- riv has joined. 15:05:36 -!- riv has quit (Remote host closed the connection). 15:05:53 -!- riv has joined. 15:13:53 -!- imode has joined. 15:17:34 -!- hendursa1 has quit (Quit: hendursa1). 15:18:16 -!- hendursaga has joined. 15:26:34 -!- chiselfuse has quit (Remote host closed the connection). 15:27:40 -!- callforjudgement has joined. 15:27:40 -!- ais523 has quit (Ping timeout: 250 seconds). 15:27:57 -!- callforjudgement has quit (Client Quit). 15:28:24 -!- chiselfuse has joined. 15:56:44 -!- wib_jonas has quit (Quit: Client closed). 16:17:40 -!- chiselfuse has quit (Remote host closed the connection). 16:17:51 -!- chiselfu1e has joined. 16:31:39 [[School]] https://esolangs.org/w/index.php?diff=87926&oldid=85635 * AceKiron * (+82) 16:42:47 [[User talk:Heavpoot]] https://esolangs.org/w/index.php?diff=87927&oldid=85250 * Martsadas * (+111) 17:04:29 fungot being a pita is no news 17:04:30 arseniiv: and china could not copy usa technology and flaunt it just keeps on growing. am a bit puzzled about why you asked 17:05:04 fungot: why, I didn’t ask anything (yet?) 17:05:04 arseniiv: what is remarkable, i think. mostly common lisp and scheme implementations ( tm)) 17:05:38 I need to write some lispy language sometime, yeah 17:05:55 that sounded like pure propaganda 17:06:11 (fungot, I mean) 17:06:11 int-e: you're suggesting cluttering the namespace with names like fnord and fnord 17:06:31 fungot: okay, no need to get insulting 17:06:31 int-e: just seems silly to construct a list; it does whatever the code surrounding the ( x y) x y 17:07:09 something far from CL and Scheme, just using S-expressions for its syntax and maybe using symbols, though good symbols might ask their full CL treatment which isn’t easy for a language developer 17:07:32 you're suggesting cluttering the namespace with names like fnord and fnord => lol 17:09:31 I agree it’s silly to construct a list; either it’s already there in platonic sense, or it’s nowhere at all, in which case trying to construct it would be in vain 17:11:31 if it’s already there, one needs to just fetch it with (get-list-from-outer-planes ) 17:12:15 if it doesn’t have any names, then I guess we’re broke 17:13:03 either it’s already there in platonic sense, or it’s nowhere at all => though I’m unnecessarily classical here. Maybe there is a third option 17:19:04 arseniiv: "what is a list" has the potential to unfold into all philosophy ever conceived and some new one 17:19:49 int-e: it better do! 17:20:14 or did 17:20:22 at some point you'll have to make a list of possible interpretations 17:20:28 just to keep track of it all 17:21:08 (not circular; you can make a list without fully understanding what it is) 17:21:39 Lists usually require infinity; they don't trivially always exist. https://ncatlab.org/nlab/show/free%20monoid explains the details. 17:22:52 Saying "lists require infinity" sounds like saying "natural numbers require infinity". 17:23:09 Where I think it's maybe more like, the style you use to talk about natural numbers requires infinity, or something. 17:24:01 In Haskell lists are certainly not free monoids (either in the standard sense or in the Haskell sense, where those are also distinct). 17:24:07 Maybe there's a more grammatical way to put it. FinSet is a topos, so it's not possible to constructively tell whether or not infinite objects really exist; we have to assume them. 17:24:17 shachaf: fortunately we can justify this claim on a ridiculously informal level: Have you ever looked at the number 8 from the side? ;-) 17:26:05 It's well-established that the Peano naturals stop at 88. 17:26:17 I think something like shachaf too. For example, though I don’t know ultrafinitist constructions, we could imagine lists of length more than N fail to exist, so cons or ++ are partial but for some reason we can’t stumble on that fact 17:26:24 oh, 88 17:27:13 Man, "what if sufficiently big numbers don't exist? we'd never know it" is a funny take on ultrafinitism. 17:27:36 -!- Koen_ has joined. 17:28:28 you'll need imaginary numbers then 17:28:38 that you imagine to exist 17:29:05 The thing that makes it funny is that it still takes some platonic notion of existence, and imagines that it applies to some numbers, and not others. I hadn't really thought of that perspective. 17:30:10 I'm not even being finitist here. It's a variation on Skolem's paradox. In order to talk about existence of objects, we need a formal mathematical logic for those objects. For questions of size/cardinality/measurement, set theory is traditional. But constructive set theory is confined within the rules of topoi, so if a topos lacks some classical property, then the property didn't exist universally in the first place. 17:30:40 Just like with Skolem's paradox, we might have taken some property of Set (say, that there's natural numbers or free monoids) and imagined that it must be universal, even though some topoi like FinSet refute it. 17:30:50 -!- src has quit (Quit: Leaving). 17:30:58 that you imagine to exist => hm then we may end up with an existence hierarchy 17:31:04 I was talking about arseniiv's thing. 17:31:16 But, hmm, I can talk about the existence of objects without a formal mathematical logic for those objects. 17:31:56 I guess. Maths just makes it easy: Every describable object exists, except for those which would contradict themselves if they existed. 17:32:21 Would you say that existence is a property that some things have and some things don't, or that everything exists? 17:32:55 I'd say that "existence" is a linguistic meme, a language-game which has a faulty assumption about the nature of reality. 17:33:51 there were some logics with two sets of quantifiers, the usual ∀ and ∃ and then “outer” ones which have strange semantics 17:34:20 Hmm, Internal Set Theory? 17:34:55 a quantified variable in those runs over inexisting things. Don’t remember if it’s connected to IST 17:35:07 ow, not inexisting things, but all things 17:35:34 I think that was for modal logics or free logics, hm 17:36:38 -!- riv has quit (Quit: Leaving). 17:37:25 "real thought" is a nice oxymoron 17:37:25 I guess I saw that here: https://plato.stanford.edu/entries/logic-free/#Meinong 17:37:37 -!- riv has joined. 17:39:44 once I thought some kind of free logic would be what I wanted an ideal classical logic to be, yet it failed when I read this article: all kinds seem to have their flaws 17:40:52 hopefully a type-theoretical framework is good. At least I haven’t seen someone discussing flaws like those for it to have 17:41:54 it's one of those "there are 15 types of logic, but they all have their flaws. i'm going to develop a new logic that unifies them all" -> "there are 16 types of logic, but they all have their flaws" 17:42:44 But it makes for a great story. https://en.wikipedia.org/wiki/Homo_narrans 17:43:20 arseniiv: The "field with one element" doesn't exist, because of the definition of fields. Nonetheless it has pages on WP and nLab, because there is a field-with-one-element-shaped-hole in projective geometry. 17:43:38 "It's well-established that the Peano naturals stop at 88." => I don't think that can satisfy the axioms 17:44:09 When combined with the fact that the category of fields is disconnected (fields of different characteristic aren't related to each other), it suggests that fields are an incomplete notion; we have the wrong definition! 17:44:17 b_jonas: that just means that the theory is flawed model of reality 17:44:23 Corbin: yeah I agree it should exist in some fashion 17:44:33 the field F₁, I mean 17:45:37 "a quantified variable in those runs over inexisting things" => is that second order logic? 17:46:08 arseniiv: oh, third possibility: does Schrödinger's cat exist? 17:46:47 Hypothetically speaking, of course ;) 17:46:51 b_jonas: no, that one is one-sorted 17:47:53 int-e: unlikely. Schrödinger died in 1961, his cat would have died and decomposed by now unless he got it mummified or put it on a relativistic speed rocket or something 17:48:18 b_jonas: seems fair 17:48:48 int-e: it, I mean the paradox itself, does in global culture, but as of the cat itself, I’d think decoherence theory gives us a very tight estimate on the time the cat’s still in superposition, like attoseconds I think 17:49:11 oh my poor grammar 17:51:54 what I wodner is, if the poison gas is released in the box to kill Schrödinger's cat, wouldn't it also kill whoever opens the box when they open it? 17:51:57 -!- delta23 has joined. 17:52:39 I guess they could be careful and use a chemistry lab smoke hood or something 17:52:46 -!- Sgeo has joined. 17:53:30 hm what if we call a Schrödinger’s cat any cat which lives in Schrödinger’s children’s homes as an unbreaking line, or a tree. Then this kind of a collective cat is probably still alive 17:54:29 or if his children all disliked cats, then not 18:17:19 -!- dyeplexer has quit (Remote host closed the connection). 18:18:58 -!- Everything has quit (Quit: leaving). 18:42:28 I'm not sure if any cat would be willing to own the family that deliberately killed with 50% probability a previous cat just for a tought experiment 18:42:50 they would certainly just pick a better choice of servent 18:49:42 -!- tech_exorcist_ has joined. 18:51:05 -!- tech_exorcist has quit (Ping timeout: 252 seconds). 19:33:18 -!- Koen_ has quit (Quit: Leaving...). 20:16:16 are there good aperiodic 1d tilesets? 20:17:27 if so, either the matching rules should be quirky, or tiles should at least be nonconnected 20:18:14 I feel it might end up not that hard to enforce for example 0 → 01, 1 → 10 blow-up rules 20:30:26 arseniiv: I don't think aperiodic 1d tilesets are possible 20:30:55 1d tiles just behave like regular languages 20:31:27 yes 20:31:31 unless perhaps it's some weird non-measurable ones, but even so I doubt they can force aperiodic 20:31:52 you can do an aperiodic 1d tiling, but there's no tile set that forces aperiodicity 20:32:07 :( 20:32:44 +finite 20:32:46 how to make a connection with regular languages clearer? 20:33:01 each tile is a transition from one state to another 20:33:03 finite, yeah, I wouldn’t want an infinite tileset 20:33:03 arseniiv: it's quite literally an NFA 20:33:15 hmmmhmhmhm 20:34:42 I see, even if a tile has many holes and connects with many previous and following tiles, it still would be a finite number of neighborhoods allowed for all of them 20:34:54 that’s sad 20:36:08 it's interesting 20:36:25 so for wang tiles to work, the pattern needs height 20:36:32 that increases without bound 20:36:44 any finite height strip would just be equivalent to a 1d tileset 20:37:05 um wait 20:37:26 ah at least this 1d thing gives an insight (if it does) 20:38:32 what if you have two tiles, one is the set of rationals between 0 and sqrt(3), the other the set of all irrationals between 0 and 1? 20:38:42 one is the set of rationals between 0 and sqrt(3), the other the set of all rationals between 0 and 1? 20:38:46 no 20:38:49 argh 20:38:55 one is the set of rationals between 0 and sqrt(3), the other the set of all irrationals between 0 and 1? 20:39:26 then you'll have to overlay the two tiles such that the first kind repeats with period sqrt(3), the second with period 1 20:39:30 of course it's cheating 20:39:45 but you should try to explain why that problem can't happen without cheating 20:39:56 wait that doesn't work 20:40:02 you have to be more evil than that 20:41:08 it has to be the set of rational linear combinations of 1 and sqrt(3) between 0 and sqrt(3) half-inclusive, and the set of numbers between 0 and 1 that are linear independent from {1,sqrt(3)} 20:41:34 -!- Corbin has quit (Ping timeout: 252 seconds). 20:41:41 well there is the projection trick 20:42:20 http://sig3.ecanews.org/isac2010/lectures/06a_fujita_tilings_a.pdf slide 13 14 20:42:50 you start with a slope of irrational gradiant and project it down 20:43:58 riv: sure, but in 1D that'll just lead to an aperiodic tiling 20:44:06 not a tileset that forces it 20:55:44 -!- Lord_of_Life_ has joined. 20:55:52 -!- Lord_of_Life has quit (Ping timeout: 252 seconds). 20:58:21 -!- Lord_of_Life_ has changed nick to Lord_of_Life. 21:00:09 can a PDA output an aperiodic string? 21:01:22 PDA doesn't output a string, it only accepts or rejects a string 21:01:38 i seee... 21:01:41 but I suppose you could easily define an output version (pushdown transducer?) 21:02:06 maybe it has to be context sensitive 21:02:49 b_jonas: You can stick to natural numbers or integers; for example, if you let X = { n | n >= 0 such that n can be written in base 4 using only digits 0 and 1}, then {X u X+2} = 4X+{0,1,2,3}, so you can tile N, and {X u X-2} = 4X+{-2,-1,0,1} so you can tile Z. Obviously those are aperiodic 21:03:00 anyway i think it could output a nonperiodic string 21:03:19 you can use the stack to count so you could do like ABBAAABBBBAAAAABBBBBB 21:03:40 and there is no bound to the stack depth 21:04:34 (so infinite tiles are a problem) 21:05:29 keegan, oh good point! i was overlooking that completely 21:05:55 i'd have to formalize it to be sure though 21:06:04 maybe it's not so easy to count because you lose the count as you consume it 21:07:38 the pumping lemma for PDAs means you can always have long stretches of periodic substrings... 21:07:42 remember also there is a difference in power between deterministic and nondeterministic PDA (unlike for finite automata or for turing machines) 21:07:55 (assuming it accepts strings of arbitrary length) 21:08:23 int-e: infinite tiles are a problem for sure, I think using disconnected tiles we could force using them like keegan’s ABBAAABBBB: 1 2 3 4 etc., something like making them each 0, 1, 2, 3, … holes and carefully assigning distances 21:08:55 (fwiw i wasn't paying attention to the earlier tiling discussion) 21:09:17 it was about if I can make a finite 1d nonperiodic tileset 21:09:24 arseniiv: what I have is similar in spirit, really; I just find it cute to make it work with a single tile (though that means you have to keep track of the positioning of the tile for "aperiodicity") 21:10:17 (but to my mind that makes sense: there's no placement of tiles that is repeated periodically) 21:10:17 int-e: I think I saw that tile somewhere, even, if I infer its construction right (I skimmed what you wrote) 21:10:35 arseniiv: it's reminiscent of the cantor set 21:13:03 int-e: something like p-adically? Oh I guess I should just read in 21:15:39 > fix (\x -> 'X':tail (x >>= \c -> [c,c,'.','.'])) 21:15:41 "XX..XX..........XX..XX..........................................XX..XX........ 21:16:17 hm wait why use 4 but not 3? 21:18:01 with digits 0 and 1? that would leave a gap of size 1 near the beginning: XX.XX.... etc. 21:18:06 and nothing to fill it 21:18:30 ah, I see, we can’t use just 1 21:18:46 and using digits 0 and 2 confuses me, but I imagine it still doesn't work 21:20:19 I mean we can take X.X...X.X.........X.X...X.X[...] and shift it by one, and that will result in XXXX..XXXX........XXXX..XXXX[...] and now we have chunks of length 4 and some gaps of length 2 21:20:31 in contrast, base 4 just works 21:21:05 -X- -X- --- --- -X- --- --- --- --- --- --- --- --- -X- --- --- --- --- --- --- --- --- --- --- --- --- --- <- with 1 in ternary 21:21:34 yeah 4 with 0 and 1 looks more comfortable 21:21:39 basically by virtue of {0,1,2,3} = {0,1}+{0,2}, where {0,1} are used as digits for the tiles and {0,2} as offsets for shifting the tiles 21:22:31 Or, for covering the integers, {-2,-1,0,1} = {0,1}+{-2,0} 21:23:33 how I like simple solutions 21:27:36 Hah, how about this abstraction as an exercise: "Find a subset X of N={0,1,...} such that the map (x,y) |-> x+2y is a bijection between XxX and N." 21:29:45 (The X from above is the only solution.) 21:32:07 would that just be the odd numbers? 21:32:29 -!- olsner has joined. 21:32:58 int-e: sure, with infinite tiles it's easy. you can make one huge infinite tile with tiny holes far from each other, where the holes are randomly 2 or 3 long, plus small 2 and 3 long tiles to fill one of those holes, and that's aperiodic too. 21:33:16 riv: no, then you don't get any even numbers as results... but also plenty of duplicates 21:33:49 you can make that work with just two tiles in fact, no need for different sizes of holes, just place the holes randomly 21:33:53 b_jonas: your tiles are effectively infinite too, by virtue of incommunserability 21:34:42 b_jonas: right. but as I said, I found the task of making a single tile work interesting 21:34:59 -!- APic has quit (Read error: Connection reset by peer). 21:35:00 difficult problem :O 21:35:41 -!- APic has joined. 21:36:45 riv: well, 0 needs to be in X (otherwise you don't get 0 as a sum)... 1 needs to be in X (otherwise you don't get 1). 2 can't be in the set (because otherwise we'd get 2+2*0 = 0+2*1... and it basically continues like that. 21:37:26 riv: at some point you'll switch to binary representation.... and look at every second digit... and that's how you get to base 4. 21:37:49 that is so cool, it's like a sudoku or something 21:38:17 I think it's doable, but it does require some technique and persistence. 21:45:56 -!- Corbin has joined. 22:02:48 -!- tech_exorcist_ has quit (Quit: see you tomorrow). 22:24:53 -!- APic has quit (Read error: Connection reset by peer). 22:25:32 -!- arseniiv has quit (Ping timeout: 245 seconds). 22:42:13 -!- APic has joined. 23:08:55 -!- sprock has quit (Read error: Connection reset by peer). 23:09:28 -!- sprock has joined.