The Calendar hole will go live in approximately 13 days. Why not try and solve it ahead of time?
Kolakoski Sequence in all languages in bytes. 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 Bytes Time Submitted 881st SirBogman 🇺🇸 666 108 72ms 3 Jan 2022 882nd Natanaelel 🇸🇪 663 56 3ms 20 Jan 2024 883rd DialFrost 🇸🇬 663 75 112ms 3 Jun 2025 884th 77Tigers 662 114 133ms 9 Apr 2024 885th Waffle3z 661 76 11ms 20 Jan 2021 885th hellwue 661 76 10ms 16 Nov 2023 885th dokutan 661 76 17ms 24 Mar 2025 888th dokutan 658 69 740ms 30 Aug 2025 889th HumanoidCPU 658 73 408ms 3 Jun 2024 890th uttumuttu 🇫🇮 656 71 9ms 8 Jan 2022 890th olleicua 🇺🇸 656 71 9ms 20 Feb 2024 892nd emgordon154 655 70 130ms 6 Sep 2024 893rd msbranicky 654 134 277ms 3 Oct 2023 894th albanian-laundromat 653 98 39ms 19 days ago 895th olivermrose 🇺🇸 652 57 3ms 24 Aug 2021 896th f-tucker 652 77 11ms 2 Feb 2024 896th undefinedRyan 652 77 11ms 19 Apr 2025 896th Emutis 🇱🇹 652 77 10ms 12 Sep 2025 899th dokutan 652 94 326ms 18 Jul 2025 900th boxjelly 649 65 38ms 11 Feb 2021 900th msbranicky 649 65 40ms 12 Sep 2023 902nd janbehrens 🇩🇪 649 135 281ms 13 Jun 2021 903rd Shanethegamer 🇺🇸 648 97 8ms 22 Dec 2023 904th jwhear 🇺🇸 647 171 1,847ms 1 Oct 2024 905th MeWhenI 🇻🇦 646 71 125ms 3 Aug 2024 906th AkashTandon167 644 78 10ms 25 May 2021 906th jhpaques 🇫🇷 644 78 21ms 30 Nov 2022 908th johnnythedoggie 644 106 107ms 3 Mar 2021 908th snoozingnewt 🇨🇦 644 106 94ms 27 days ago 910th SirBogman 🇺🇸 643 84 2ms 14 Dec 2021 911th annaproxy 642 93 95ms 24 Dec 2022 912th MateuszPietrzak 🇵🇱 642 112 67ms 16 Jan 2024 913th NickTheEASDude 🇺🇸 641 95 1ms 1 Jul 2024 914th emgordon154 641 98 10ms 10 Dec 2024 915th CaedenHarper 🇨🇦 641 107 520ms 6 Oct 2025 916th nephila-nacrea 🇬🇧 640 58 3ms 3 Feb 2021 917th KatieLG 🇬🇧 640 77 222ms 2 Oct 2022 918th alomiF 640 102 124ms 4 Nov 2024 919th Bubbler-4 639 97 72ms 13 Sep 2023 920th Maznek 638 73 10ms 30 Jun 2023 921st MeWhenI 🇻🇦 637 82 10ms 21 Jul 2023 922nd ashtraypettingzoo 🇺🇸 636 36 32ms 23 Feb 2023 923rd twocatsinatrenchcoat 636 79 9ms 29 Mar 2022 923rd SniperSmiley 🇺🇸 636 79 35ms 23 Jun 2022 923rd Glinte 636 79 16ms 14 Dec 2023 923rd Bmrl7 636 79 14ms 19 Mar 2024 927th Shanethegamer 🇺🇸 635 57 246ms 27 Jul 2023 928th sreyfe 635 119 162ms 9 Jun 2024 929th edsrzf 🇳🇿 635 138 273ms 21 Dec 2024 930th SirFireball3521 632 58 142ms 2 Mar 2023 931st dokutan 632 76 460ms 24 Mar 2025 932nd MeWhenI 🇻🇦 632 90 4,253ms 24 Oct 2024 933rd emgordon154 632 186 661ms 30 May 2025 934th NewDefectus 🇮🇱 630 59 6ms 25 Oct 2021 935th janbehrens 🇩🇪 629 136 25ms 9 Jul 2021 936th bastienvoirin 🇫🇷 628 80 16ms 4 Feb 2021 936th argusdusty 🇺🇸 628 80 17ms 25 Mar 2021 936th OppositeShark 628 80 11ms 9 Apr 2022 936th WillowWispy 628 80 9ms 16 Mar 2025 940th AkashTandon167 628 86 2ms 25 May 2021 941st Shanethegamer 🇺🇸 625 64 2ms 26 Jul 2023 942nd emgordon154 622 151 8ms 6 Oct 2024 943rd Herbert00709 🇵🇱 621 87 2ms 19 Nov 2024 944th janbehrens 🇩🇪 620 68 54ms 18 Jan 2021 945th vodker1 620 81 10ms 9 Mar 2022 945th tooningelaere 620 81 9ms 5 Dec 2022 947th Yewzir 🇧🇪 619 64 5ms 16 Nov 2023 948th dokutan 618 106 11ms 24 Mar 2025 949th Shanethegamer 🇺🇸 614 85 4ms 21 Dec 2024 950th Natanaelel 🇸🇪 614 88 2ms 9 May 2024 951st codename68 614 123 136ms 13 Aug 2022 952nd orthoplex 🇨🇽 613 153 19ms 25 Jun 2023 953rd fynnkroeger 612 82 10ms 24 Mar 2021 953rd BrenSchaap 612 82 10ms 21 Oct 2021 953rd MichaelMBradley 🇨🇦 612 82 10ms 18 Feb 2022 953rd Andrey2001 612 82 11ms 12 days ago 957th primo-ppcg 🇹🇭 612 112 388ms 2 Aug 2021 957th Lydxn 🇨🇦 612 112 381ms 28 Feb 2022 959th Shanethegamer 🇺🇸 612 192 486ms 2 Apr 2025 960th omurakazuaki 🇯🇵 611 69 43ms 19 Feb 2021 First Prev 881–960 of 1,887 Next Last