The Calendar hole will go live in approximately 6 days. Why not try and solve it ahead of time?
Pernicious Numbers in Ruby 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 1st prplz 🇦🇺 1,000 28 41ms 3 Jan 2020 1st primo-ppcg 🇹🇭 1,000 28 45ms 3 Jan 2020 1st stefangimmillaro 1,000 28 36ms 11 Dec 2024 1st radarek 🇵🇱 1,000 28 36ms 17 Dec 2024 1st pardouin 🇫🇷 1,000 28 42ms 12 Apr 2025 6th NewDefectus 🇮🇱 966 29 40ms 8 May 2021 6th akshatj27 🇦🇶 966 29 35ms 11 Jan 2022 6th m-tkach 🇺🇦 966 29 40ms 23 Nov 2022 6th Steffan153 🇫🇮 966 29 40ms 1 Jan 2023 6th DialFrost 🇸🇬 966 29 38ms 13 Jan 2023 6th sean-niemann 🇺🇸 966 29 36ms 29 Jan 2023 6th MeWhenI 🇻🇦 966 29 35ms 30 Jan 2023 6th JayXon 🇺🇸 966 29 36ms 25 Dec 2023 6th sisyphus-ppcg 🇦🇺 966 29 33ms 25 Dec 2023 6th Yewzir 🇧🇪 966 29 38ms 25 Dec 2023 6th GrayJoKing 🇦🇺 966 29 40ms 26 Dec 2023 6th Lydxn 🇨🇦 966 29 39ms 29 Dec 2023 6th xsot 🇸🇬 966 29 39ms 30 Dec 2023 6th fuzzylojik-golf 🇺🇸 966 29 42ms 30 Aug 2025 6th snoozingnewt 🇨🇦 966 29 48ms 21 days ago 21st Waffle3z 933 30 39ms 10 Feb 2021 21st lynn 933 30 36ms 11 Sep 2021 21st Irratix 🇳🇱 933 30 37ms 22 Mar 2022 21st orthoplex 🇨🇽 933 30 40ms 30 Mar 2022 21st SirBogman 🇺🇸 933 30 46ms 31 May 2022 21st inventshah 933 30 39ms 18 Jun 2022 21st jared-hughes 933 30 37ms 10 Sep 2022 21st Shanethegamer 🇺🇸 933 30 37ms 6 Feb 2023 21st ovs-code 🇩🇪 933 30 38ms 17 Jul 2023 21st Betuaredead 933 30 36ms 11 Nov 2023 21st dokutan 933 30 37ms 26 Mar 2024 21st BREMAUCY 🇫🇷 933 30 38ms 14 May 2024 21st FlyingPenguin223 933 30 40ms 23 Oct 2024 21st emgordon154 933 30 39ms 18 Mar 2025 21st edsrzf 🇳🇿 933 30 47ms 26 Jul 2025 21st CaedenHarper 🇨🇦 933 30 35ms 13 Sep 2025 21st blaztoma 🇱🇹 933 30 34ms 6 days ago 38th Natanaelel 🇸🇪 875 32 45ms 25 Jun 2022 38th AlephSquirrel 875 32 34ms 7 Mar 2023 40th janlelis 848 33 43ms 9 Feb 2021 41st Yax42 🇫🇷 824 34 35ms 4 Oct 2025 42nd annaproxy 757 37 38ms 27 Aug 2022 42nd OhmNomNom 757 37 39ms 15 Oct 2022 42nd error256 757 37 38ms 24 hours ago 45th Andriamanitra 🇫🇮 737 38 35ms 23 Sep 2022 46th j55d 718 39 37ms 11 Dec 2017 47th hiddicop 🇸🇪 700 40 44ms 30 Jan 2021 48th olivermrose 🇺🇸 683 41 42ms 20 Oct 2021 48th yzhs 🇩🇪 683 41 41ms 20 Jul 2022 48th Lv0Sys 🇵🇱 683 41 36ms 26 days ago 51st anter69 🇭🇺 667 42 36ms 24 Jan 2023 51st rucin93 🇵🇱 667 42 38ms 12 Jan 2024 53rd tatzyr 🇯🇵 636 44 34ms 28 Mar 2025 54th proton 🇩🇪 622 45 39ms 9 Jun 2020 54th KatieLG 🇬🇧 622 45 35ms 10 Apr 2022 54th 4hg 🇺🇸 622 45 35ms 20 Oct 2022 54th janbehrens 🇩🇪 622 45 43ms 27 Nov 2022 58th daninnm 609 46 35ms 23 Jul 2021 58th Babafaba 609 46 38ms 15 Oct 2025 60th gilufin 596 47 42ms 8 Aug 2021 60th fynnkroeger 596 47 36ms 17 Apr 2023 62nd Haksell 🇦🇶 583 48 36ms 13 Apr 2020 62nd jaredcrystal 🇺🇸 583 48 48ms 14 Dec 2020 62nd ejini6969 583 48 36ms 14 Jun 2025 65th sk- 571 49 39ms 12 Sep 2019 65th eggplants 🇯🇵 571 49 36ms 26 Nov 2020 67th n1LS 560 50 36ms 2 Oct 2019 68th biinari 549 51 34ms 25 Mar 2018 69th boxjelly 509 55 34ms 9 Feb 2021 69th csharpython 509 55 43ms 5 Aug 2025 71st vonagam 500 56 46ms 8 Nov 2017 71st hrrs01 500 56 48ms 26 Sep 2018 71st tadd 500 56 45ms 16 Apr 2020 71st Pluviolithic 500 56 37ms 23 Jul 2025 75th iamsolarpowered 491 57 36ms 15 Dec 2017 75th graft 491 57 43ms 11 Mar 2018 77th yokasuretsu 483 58 37ms 16 Apr 2018 77th reireias 483 58 37ms 30 Jul 2019 79th caerbannogwhite 475 59 36ms 13 Apr 2018 79th handisb 475 59 37ms 26 Oct 2019 1–80 of 118 Next Last