The Calendar hole will go live in approximately 10 days. Why not try and solve it ahead of time?
Kolakoski Sequence 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 801st typeswitch-dev 🇵🇹 705 74 8ms 7 Aug 2023 802nd antimon2 🇯🇵 704 65 635ms 19 Jan 2021 802nd msbranicky 704 65 1,074ms 12 Sep 2023 804th osmith93 704 70 25ms 14 Jun 2021 804th ridingqwerty 🇺🇸 704 70 12ms 23 Feb 2024 804th mbittner20 704 70 13ms 15 Jul 2024 804th RaBa21 🇭🇺 704 70 11ms 18 Jul 2025 808th Shanethegamer 🇺🇸 704 91 39ms 16 Jun 2022 809th Herbert00709 🇵🇱 704 101 84ms 19 Nov 2024 810th SnowballSH 703 60 44ms 12 Feb 2021 810th aksyristos 703 60 39ms 28 Feb 2023 810th Lv0Sys 🇵🇱 703 60 56ms 17 days ago 813th MeWhenI 🇻🇦 702 238 12ms 29 Aug 2023 814th UnderKoen 🇳🇱 700 134 12ms 20 Jan 2025 815th jared-hughes 699 44 7ms 31 Jul 2022 816th NewDefectus 🇮🇱 699 76 2ms 25 Oct 2021 816th JohandeRuiter 🇳🇱 699 76 2ms 3 Dec 2023 818th Shanethegamer 🇺🇸 699 77 13ms 9 Oct 2023 819th targrik 698 123 271ms 10 Jul 2025 820th AlephSquirrel 696 34 48ms 30 Dec 2022 821st neihousaigaai 696 67 10ms 10 Apr 2021 822nd Jacob385 696 69 398ms 22 Apr 2024 823rd jared-hughes 696 159 1,670ms 16 Sep 2025 824th DialFrost 🇸🇬 695 56 84ms 22 Jul 2024 825th targrik 695 57 5ms 26 Aug 2025 826th SnowballSH 694 71 11ms 12 Feb 2021 826th Andre3582 694 71 10ms 18 Mar 2021 826th PhysicDev 🇫🇷 694 71 11ms 20 May 2021 826th Alban-Boissard 694 71 12ms 10 Jun 2025 830th boxjelly 694 94 114ms 21 Jan 2021 830th YAJUE114514 694 94 133ms 24 Jul 2025 832nd Espiobest 691 61 37ms 13 Feb 2021 832nd DaCuteRaccoon 691 61 40ms 9 Dec 2022 834th edsrzf 🇳🇿 691 91 19ms 21 Dec 2024 835th JGDoerrer 690 103 474ms 5 Jan 2022 835th tailorspy 690 103 62ms 29 Oct 2023 837th Shanethegamer 🇺🇸 690 106 17ms 4 Oct 2024 838th msbranicky 689 95 5ms 11 Aug 2023 839th NewDefectus 🇮🇱 688 32 34ms 20 Dec 2021 840th GolfingSuccess 🇬🇷 688 69 33ms 17 Aug 2024 841st Andriamanitra 🇫🇮 687 95 148ms 20 Jul 2023 842nd KasperKivimaeki 🇫🇮 687 125 260ms 3 Oct 2025 843rd msbranicky 685 89 1ms 26 Sep 2023 844th LeeCamp 684 72 11ms 16 Feb 2022 844th LukasFolwarczny 🇨🇿 684 72 11ms 16 Sep 2022 844th CutSandstone 684 72 36ms 8 Jul 2024 847th dokutan 678 59 3ms 18 Jul 2025 848th Shanethegamer 🇺🇸 678 126 24ms 8 Jul 2021 849th jared-hughes 676 35 44ms 31 Jul 2022 849th Natanaelel 🇸🇪 676 35 49ms 18 Aug 2022 851st SirBogman 🇺🇸 676 44 314ms 22 Oct 2021 852nd Yewzir 🇧🇪 676 88 327ms 14 Oct 2023 853rd richard-oelze 🇩🇪 675 73 29ms 4 Apr 2021 853rd mauro-1 🇮🇹 675 73 9ms 18 Aug 2021 853rd gchenfc 675 73 9ms 24 Jan 2022 853rd hiichbindermax 675 73 11ms 26 Feb 2022 853rd Omega65536 🇩🇪 675 73 11ms 24 Nov 2022 853rd sandorstormen 675 73 11ms 18 Feb 2023 853rd Mr-McChicken 675 73 11ms 15 Oct 2023 853rd Masttest 675 73 10ms 21 Feb 2024 861st dokutan 675 99 805ms 24 Sep 2025 862nd janbehrens 🇩🇪 673 68 1,067ms 9 Apr 2021 863rd madex 🇩🇪 672 79 2ms 11 Jul 2024 864th msbranicky 672 80 4ms 11 Oct 2023 865th rboath 671 58 88ms 8 Jan 2025 866th 5quiwyrm 670 54 254ms 5 Dec 2024 867th I-Love-47 🇺🇦 670 106 63ms 10 Feb 2022 868th CaedenHarper 🇨🇦 666 70 9ms 31 Jan 2025 869th jameslindesay 666 74 11ms 24 Feb 2021 869th PkmnQ 666 74 37ms 5 May 2024 869th RedzGoose 🇦🇺 666 74 13ms 14 Oct 2024 869th yokasuretsu 666 74 10ms 13 Jan 2025 873rd Natanaelel 🇸🇪 663 56 3ms 20 Jan 2024 874th MeWhenI 🇻🇦 663 69 397ms 15 Feb 2023 874th MarcMush 🇫🇷 663 69 456ms 12 Feb 2024 874th Yewzir 🇧🇪 663 69 483ms 5 Apr 2024 877th DialFrost 🇸🇬 663 75 112ms 3 Jun 2025 878th 77Tigers 662 114 133ms 9 Apr 2024 879th dokutan 660 69 740ms 30 Aug 2025 880th SirBogman 🇺🇸 658 108 72ms 3 Jan 2022 First Prev 801–880 of 1,871 Next Last