The Calendar hole will go live in approximately 7 days. Why not try and solve it ahead of time?
Kolakoski Constant in all languages in chars. Achievements Cheevos Holes Languages Medals Miscellaneous All Holes 12 Days of Christmas 24 Game 99 Bottles of Beer Abundant Numbers Abundant Numbers (Long) Arabic to Roman Arithmetic Numbers Arrows Ascending Primes ASCII Table Billiards brainfuck Card Number Validation Catalan Numbers Catalan’s Constant Christmas Trees Collatz CSS Colors Cubes Day of Week DFA Simulator Diamonds Divisors Emirp Numbers Emirp Numbers (Long) Emojify Evil Numbers Evil Numbers (Long) Factorial Factorisation Farey Sequence Fibonacci Fizz Buzz Foo Fizz Buzz Bar Forsyth–Edwards Notation Fractions Game of Life Gijswijt’s Sequence Happy Numbers Happy Numbers (Long) Hexdump Hilbert Curve Intersection Inventory Sequence ISBN Jacobi Symbol Kaprekar Numbers Kolakoski Constant Kolakoski Sequence Leap Years Levenshtein Distance Leyland Numbers ln 2 Look and Say Lucky Numbers Lucky Tickets Mahjong Mandelbrot Maze Medal Tally Minesweeper Morse Decoder Morse Encoder Musical Chords N Queens Niven Numbers Niven Numbers (Long) Number Spiral Odious Numbers Odious Numbers (Long) Ordinal Numbers PalindromemordnilaP Pangram Grep Partition Numbers Pascal’s Triangle Pernicious Numbers Pernicious Numbers (Long) Poker Polyominoes Prime Numbers Prime Numbers (Long) Proximity Grid QR Decoder Quine Recamán Repeating Decimals Reverse Polish Notation Reversi Rijndael S-box Rock-paper-scissors-Spock-lizard Roman to Arabic ROT13 Rule 110 Scrambled Sort Set Seven Segment SI Units Sierpiński Triangle Smith Numbers Spelling Numbers Star Wars GPT Star Wars Opening Crawl Sudoku Sudoku (Fill-in) Ten-pin Bowling Tic-tac-toe Time Distance Tongue-twisters Topological Sort Tower of Hanoi Transpose Sentence Trinomial Triangle United States Vampire Numbers Van Eck Sequence Zeckendorf Representation Zodiac Signs γ λ π τ φ √2 𝑒 Apéry’s Constant Binary Lambda Calculus Calendar Connect Four Continued Fractions Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers Multitap Input NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial All Languages ><> Assembly AWK Bash BASIC Berry brainfuck C C# C++ Civet Clojure COBOL Coconut Common Lisp Crystal D Dart Elixir Erlang F# Factor Forth Fortran Gleam Go GolfScript Groovy Haskell Hexagony J Janet Java JavaScript jq Julia K Kotlin Lua Nim OCaml Pascal Perl PHP PowerShell Prolog Python R Raku Rockstar Ruby Rust Scheme sed SQL Swift Tcl TeX V VimL Wren Zig 05AB1E ALGOL 68 APL Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight Luau Odin Picat Qore Racket Rebol Rexx Scala Squirrel Stax Uiua Umka Vala Vyxal Bytes Chars Scoring Bytes Chars Language All ><> Assembly AWK Bash BASIC Berry brainfuck C C# C++ Civet Clojure COBOL Coconut Common Lisp Crystal D Dart Elixir Erlang F# Factor Forth Fortran Gleam Go GolfScript Groovy Haskell Hexagony J Janet Java JavaScript jq Julia K Kotlin Lua Nim OCaml Pascal Perl PHP PowerShell Prolog Python R Raku Rockstar Ruby Rust Scheme sed SQL Swift Tcl TeX V VimL Wren Zig Experimental Language 05AB1E ALGOL 68 APL Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight Luau Odin Picat Qore Racket Rebol Rexx Scala Squirrel Stax Uiua Umka Vala Vyxal Hole All 12 Days of Christmas 24 Game 99 Bottles of Beer Abundant Numbers Abundant Numbers (Long) Arabic to Roman Arithmetic Numbers Arrows Ascending Primes ASCII Table Billiards brainfuck Card Number Validation Catalan Numbers Catalan’s Constant Christmas Trees Collatz CSS Colors Cubes Day of Week DFA Simulator Diamonds Divisors Emirp Numbers Emirp Numbers (Long) Emojify Evil Numbers Evil Numbers (Long) Factorial Factorisation Farey Sequence Fibonacci Fizz Buzz Foo Fizz Buzz Bar Forsyth–Edwards Notation Fractions Game of Life Gijswijt’s Sequence Happy Numbers Happy Numbers (Long) Hexdump Hilbert Curve Intersection Inventory Sequence ISBN Jacobi Symbol Kaprekar Numbers Kolakoski Constant Kolakoski Sequence Leap Years Levenshtein Distance Leyland Numbers ln 2 Look and Say Lucky Numbers Lucky Tickets Mahjong Mandelbrot Maze Medal Tally Minesweeper Morse Decoder Morse Encoder Musical Chords N Queens Niven Numbers Niven Numbers (Long) Number Spiral Odious Numbers Odious Numbers (Long) Ordinal Numbers PalindromemordnilaP Pangram Grep Partition Numbers Pascal’s Triangle Pernicious Numbers Pernicious Numbers (Long) Poker Polyominoes Prime Numbers Prime Numbers (Long) Proximity Grid QR Decoder Quine Recamán Repeating Decimals Reverse Polish Notation Reversi Rijndael S-box Rock-paper-scissors-Spock-lizard Roman to Arabic ROT13 Rule 110 Scrambled Sort Set Seven Segment SI Units Sierpiński Triangle Smith Numbers Spelling Numbers Star Wars GPT Star Wars Opening Crawl Sudoku Sudoku (Fill-in) Ten-pin Bowling Tic-tac-toe Time Distance Tongue-twisters Topological Sort Tower of Hanoi Transpose Sentence Trinomial Triangle United States Vampire Numbers Van Eck Sequence Zeckendorf Representation Zodiac Signs γ λ π τ φ √2 𝑒 Experimental Hole Apéry’s Constant Binary Lambda Calculus Calendar Connect Four Continued Fractions Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers Multitap Input NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial # Golfer Points Chars Time Submitted 481st dokutan 471 229 1ms 1 May 2024 482nd neihousaigaai 470 275 565ms 5 Jan 2022 483rd Yewzir 🇧🇪 469 242 353ms 11 Feb 2024 484th jared-hughes 466 233 2,028ms 17 Jul 2022 485th LukasFolwarczny 🇨🇿 462 126 12ms 16 Sep 2022 486th osmith93 458 127 61ms 10 Jul 2022 487th TheZwierzLF 🇵🇱 457 107 2,833ms 3 days ago 488th Shanethegamer 🇺🇸 457 248 361ms 12 Dec 2021 489th eranws 456 150 44ms 2 Nov 2022 490th janbehrens 🇩🇪 455 150 425ms 3 Dec 2023 491st dokutan 455 249 359ms 21 Aug 2024 492nd adamnielson42 🇺🇸 453 93 21ms 20 Nov 2023 493rd yokasuretsu 448 130 31ms 13 Jan 2025 493rd WillowWispy 448 130 13ms 16 Mar 2025 495th LucaArgentiUCF 🇮🇹 448 294 106ms 28 Jan 2021 496th NickTheEASDude 🇺🇸 444 131 188ms 20 Aug 2024 497th h3ra993huskp 🇯🇵 444 291 641ms 24 days ago 498th MeWhenI 🇻🇦 440 399 25ms 10 Jul 2021 499th dokutan 438 219 3,011ms 23 Oct 2024 500th dokutan 438 231 1,242ms 23 Aug 2024 501st hiddicop 🇸🇪 437 112 71ms 29 Jan 2021 502nd Shanethegamer 🇺🇸 437 113 223ms 4 Dec 2022 503rd jacekwladzinski 437 133 11ms 9 Oct 2025 504th madex 🇩🇪 432 250 36ms 27 Oct 2024 505th glesnick 431 135 170ms 18 Aug 2022 506th boxjelly 430 201 145ms 26 Jan 2021 507th jacobly0 🇺🇸 429 275 2ms 21 Sep 2023 508th MeWhenI 🇻🇦 428 223 40ms 3 Sep 2024 509th Pyroan 422 138 98ms 14 May 2025 509th InigoK 🇺🇸 422 138 31ms 25 Aug 2025 511th dokutan 422 226 41ms 24 Aug 2024 512th michelebastione 🇮🇹 419 139 70ms 10 Apr 2021 512th cubed-guy 419 139 24ms 2 Nov 2022 514th dokutan 417 218 6ms 5 May 2024 515th SniperSmiley 🇺🇸 416 140 95ms 30 Jun 2022 515th StefanHabel 🇨🇦 416 140 65ms 21 Apr 2024 517th MeWhenI 🇻🇦 416 209 80ms 13 Dec 2022 518th TheZwierzLF 🇵🇱 412 142 2,667ms 3 days ago 519th RYNO8 410 142 14ms 4 Sep 2021 520th Yewzir 🇧🇪 410 203 69ms 9 Mar 2024 521st MeWhenI 🇻🇦 408 724 9ms 28 Nov 2023 522nd albanian-laundromat 404 333 936ms 8 Sep 2025 523rd Yewzir 🇧🇪 403 207 71ms 7 Jul 2023 524th m-tkach 🇺🇦 401 145 113ms 19 Sep 2021 525th dokutan 400 425 41ms 23 days ago 526th neihousaigaai 398 146 19ms 8 Apr 2021 526th AGoyet 398 146 25ms 29 Jun 2022 528th Yewzir 🇧🇪 397 210 996ms 18 Feb 2024 529th RDShah 396 147 181ms 19 Jan 2021 530th dokutan 392 445 1,653ms 21 Oct 2025 531st dokutan 390 703 10ms 28 Jun 2025 532nd MeWhenI 🇻🇦 389 202 13ms 15 Nov 2021 533rd cure-honey 🇯🇵 389 338 112ms 23 Mar 2021 534th Schmitt-Very-Cool 387 334 1,059ms 1 Oct 2025 535th boxjelly 385 127 647ms 12 Feb 2021 536th Indivicivet 385 151 386ms 26 Oct 2021 537th TheZwierzLF 🇵🇱 383 152 2,053ms 3 days ago 538th Yewzir 🇧🇪 383 205 14ms 11 Nov 2023 539th hiddicop 🇸🇪 380 153 13ms 29 Jan 2021 539th ahmetdemirag 🇨🇾 380 153 476ms 16 Apr 2025 541st aksyristos 370 132 994ms 17 Nov 2024 542nd LeeCamp 366 159 17ms 16 Feb 2022 543rd boxjelly 361 161 79ms 21 Jan 2021 543rd za3k 361 161 101ms 28 Oct 2022 545th dokutan 358 390 4ms 1 Apr 2024 546th emgordon154 357 642 4ms 11 Jul 2024 547th aksyristos 355 164 127ms 26 Jan 2023 548th msbranicky 352 166 503ms 17 Jan 2024 549th adamnielson42 🇺🇸 352 194 17ms 25 Apr 2023 550th KatieLG 🇬🇧 352 425 72ms 22 Jan 2023 551st msbranicky 350 166 44ms 19 Aug 2023 552nd MeWhenI 🇻🇦 349 180 788ms 15 Sep 2025 553rd MaxElf999 346 168 367ms 27 Sep 2022 554th zakariamouhid 344 199 57ms 24 Jun 2023 555th MeWhenI 🇻🇦 339 265 1,063ms 12 Nov 2022 556th Yewzir 🇧🇪 337 270 28ms 22 Dec 2023 557th dokutan 329 409 36ms 14 Jun 2024 558th MarcMush 🇫🇷 328 581 4ms 5 Feb 2024 559th bwat2 324 399 551ms 4 Mar 2022 560th Flekay 🇩🇪 321 181 18ms 10 Jul 2025 First Prev 481–560 of 1,691 Next Last