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 640th olivermrose 🇺🇸 781 54 42ms 28 Sep 2021 640th KatieLG 🇬🇧 781 54 38ms 9 Jan 2023 640th Andriamanitra 🇫🇮 781 54 47ms 20 Jul 2023 644th GrayJoKing 🇦🇺 781 68 2ms 21 Jan 2021 644th m-tkach 🇺🇦 781 68 5ms 25 Apr 2022 644th MeWhenI 🇻🇦 781 68 2ms 11 Nov 2022 647th janbehrens 🇩🇪 781 91 64ms 20 Nov 2022 647th snyderek 🇺🇸 781 91 62ms 21 Nov 2024 647th dokutan 781 91 83ms 18 Jul 2025 650th DialFrost 🇸🇬 780 142 1,630ms 13 Sep 2025 651st MeWhenI 🇻🇦 779 88 416ms 28 Feb 2022 652nd Shanethegamer 🇺🇸 778 106 33ms 20 Jan 2025 653rd rak1507 🇬🇧 777 60 9ms 20 Jan 2021 653rd Shanethegamer 🇺🇸 777 60 9ms 26 Sep 2021 653rd duckyluuk 🇳🇱 777 60 9ms 4 Oct 2024 656th anter69 🇭🇺 776 59 982ms 24 Feb 2023 656th SirBogman 🇺🇸 776 59 1,152ms 10 Jun 2024 658th scpchicken 🇵🇼 774 48 3ms 15 Dec 2022 659th commandblockguy 🇺🇸 774 62 425ms 15 Jan 2024 659th HumanoidCPU 774 62 358ms 3 Jun 2024 661st ovs-code 🇩🇪 774 142 12ms 31 Mar 2023 662nd GrayJoKing 🇦🇺 771 55 135ms 6 Aug 2024 663rd Shanethegamer 🇺🇸 771 89 457ms 26 Jul 2023 664th mousetail 🇳🇱 771 98 116ms 3 Oct 2024 665th NewDefectus 🇮🇱 770 24 4ms 25 Oct 2021 666th MeWhenI 🇻🇦 770 47 259ms 28 Jan 2023 667th RDShah 770 64 10ms 17 Jan 2021 667th andre-lameirinhas 🇵🇹 770 64 10ms 22 Feb 2021 667th stertooy 🇧🇪 770 64 10ms 10 Jun 2024 667th Terobero 770 64 20ms 6 Sep 2024 667th moustave 770 64 11ms 5 May 2025 667th Code-Coder-coder 770 64 11ms 26 days ago 667th Lv0Sys 🇵🇱 770 64 10ms 16 days ago 674th MeWhenI 🇻🇦 767 89 104ms 25 Dec 2022 675th LostSyntax21 🇬🇧 766 55 62ms 2 Oct 2024 676th retrohun 765 63 102ms 23 Jan 2023 677th Shanethegamer 🇺🇸 765 65 108ms 22 May 2021 678th lynn 765 78 150ms 16 Nov 2021 679th Waffle3z 764 61 9ms 20 Jan 2021 679th didion0 🇺🇸 764 61 9ms 9 Feb 2021 679th KrausRaus 🇺🇸 764 61 10ms 19 Feb 2021 679th tayloia 🇬🇧 764 61 8ms 29 May 2022 683rd Shanethegamer 🇺🇸 764 93 68ms 12 Jan 2022 684th MeWhenI 🇻🇦 764 108 27ms 7 Jun 2023 685th SirBogman 🇺🇸 763 31 46ms 7 Oct 2022 686th Steffan153 🇫🇮 763 51 80ms 18 Dec 2022 687th Shanethegamer 🇺🇸 763 60 430ms 2 Jul 2021 687th alemelis 763 60 2,138ms 14 Aug 2024 689th dokutan 762 63 390ms 1 Apr 2025 690th DialFrost 🇸🇬 762 86 5ms 10 Oct 2023 691st albanian-laundromat 759 60 718ms 1 Oct 2025 692nd c0d3-4-F00d 🇩🇪 759 70 2ms 18 Mar 2022 692nd Alex-x90 🇺🇸 759 70 2ms 6 Mar 2023 692nd dokutan 759 70 5ms 18 Jul 2025 695th SirBogman 🇺🇸 759 86 115ms 24 Jan 2021 695th strout 759 86 124ms 15 Dec 2023 697th TobyBoyne 🇬🇧 758 65 10ms 21 Jan 2021 697th 77Tigers 758 65 30ms 1 Mar 2021 697th knutae 🇳🇴 758 65 10ms 29 Jun 2021 697th ehulinsky 🇺🇸 758 65 13ms 10 Nov 2021 697th guilhem-roy 🇫🇷 758 65 10ms 28 Feb 2022 697th martinnorling 🇸🇪 758 65 10ms 8 Mar 2022 697th IshanPanpaliya 758 65 10ms 3 May 2023 697th nooberitess 758 65 11ms 8 Apr 2025 705th GolfingSuccess 🇬🇷 758 71 6ms 16 Oct 2023 705th Yewzir 🇧🇪 758 71 3ms 19 Nov 2025 707th kcinnu 🇱🇹 758 146 1,731ms 17 May 2024 708th duckyluuk 🇳🇱 756 73 7ms 16 Dec 2024 709th Shanethegamer 🇺🇸 754 63 4ms 13 Aug 2024 709th emgordon154 754 63 4ms 25 Aug 2024 711th ovs-code 🇩🇪 754 87 106ms 8 Mar 2024 712th lynn 753 85 1,315ms 12 Sep 2021 713th ScottHamper 752 62 9ms 1 Jun 2021 713th helbling 🇨🇭 752 62 10ms 2 Oct 2024 715th RockOfStone 752 81 2ms 4 Nov 2021 715th dokutan 752 81 2ms 18 Jul 2025 717th Mabeloid 🇳🇴 750 64 539ms 17 Sep 2024 718th cipharius 750 87 198ms 19 Jan 2021 719th Lydxn 🇨🇦 750 223 13ms 24 Jun 2021 720th Yewzir 🇧🇪 748 71 3ms 14 Oct 2023 First Prev 641–720 of 1,870 Next Last