The Calendar hole will go live in approximately 12 days. Why not try and solve it ahead of time?
Pernicious Numbers (Long) 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 800th MeWhenI 🇻🇦 724 123 274ms 9 Apr 2024 802nd jhpaques 🇫🇷 723 70 18ms 30 Nov 2022 802nd michelebastione 🇮🇹 723 70 17ms 7 Dec 2022 802nd Skwerl23 723 70 22ms 5 Feb 2023 802nd celiendonze 🇨🇭 723 70 17ms 21 Apr 2023 802nd epic-programmer-guy 723 70 17ms 20 Dec 2023 802nd Stockoh 🇫🇷 723 70 267ms 24 Apr 2024 802nd CutSandstone 723 70 16ms 5 Jul 2024 802nd Andrey135296 723 70 16ms 25 Oct 2024 802nd Emutis 🇱🇹 723 70 19ms 27 Oct 2024 811th primo-ppcg 🇹🇭 721 43 352ms 20 Nov 2022 812th snoozingnewt 🇨🇦 720 68 119ms 8 Oct 2023 812th rboath 720 68 2,066ms 11 Dec 2024 814th Alex-x90 🇺🇸 718 75 4ms 20 Nov 2022 814th Irratix 🇳🇱 718 75 4ms 14 Jan 2023 814th Vinterion 718 75 4ms 19 Jul 2024 817th prplz 🇦🇺 718 86 243ms 16 Jan 2023 818th msbranicky 718 124 272ms 3 Oct 2023 819th MeWhenI 🇻🇦 715 36 421ms 30 Dec 2023 820th dokutan 715 72 2,687ms 3 days ago 821st edsrzf 🇳🇿 715 82 29ms 9 Sep 2025 822nd syntax-rules 714 75 52ms 15 May 2023 823rd Alex-x90 🇺🇸 713 62 12ms 14 Jan 2023 823rd m-tkach 🇺🇦 713 62 13ms 20 Mar 2023 823rd emgordon154 713 62 12ms 19 Mar 2025 823rd Yax42 🇫🇷 713 62 11ms 6 Sep 2025 827th Fishron 713 71 17ms 29 Nov 2022 827th wobblybits 713 71 19ms 29 Aug 2025 829th inventshah 712 64 137ms 4 Aug 2024 830th 4hg 🇺🇸 710 58 54ms 11 Dec 2022 830th csharpython 710 58 62ms 5 Aug 2025 832nd brimstonetrader 710 87 282ms 24 Dec 2023 833rd RYNO8 709 76 3ms 20 Aug 2023 834th sean-niemann 🇺🇸 709 87 46ms 21 Apr 2023 835th msbranicky 708 161 1,703ms 16 Sep 2025 836th dokutan 706 34 37ms 21 Aug 2024 837th CaedenHarper 🇨🇦 705 99 513ms 3 Oct 2025 838th masflam 704 59 431ms 21 Jun 2024 839th mbittner20 703 72 17ms 27 May 2023 839th eiburns 703 72 19ms 27 Oct 2023 839th WillowWispy 703 72 17ms 14 Mar 2025 842nd yzhs 🇩🇪 702 88 195ms 26 Jun 2023 843rd Yewzir 🇧🇪 701 80 100ms 12 Feb 2024 844th Steffan153 🇫🇮 700 66 20ms 14 Feb 2024 845th dokutan 700 71 43ms 18 Nov 2025 846th tatzyr 🇯🇵 698 59 55ms 17 Nov 2024 846th ejini6969 698 59 59ms 14 Jun 2025 848th janbehrens 🇩🇪 698 92 364ms 17 Apr 2025 848th MeWhenI 🇻🇦 698 92 385ms 19 Jun 2025 850th Shanethegamer 🇺🇸 696 77 55ms 30 Nov 2022 851st msbranicky 693 60 454ms 15 Jan 2024 851st alemelis 693 60 539ms 29 Aug 2024 853rd MeWhenI 🇻🇦 693 100 434ms 9 Apr 2024 854th Florian-Mt 692 99 131ms 12 Jul 2024 855th Steffan153 🇫🇮 691 74 10ms 20 Nov 2022 856th MeWhenI 🇻🇦 691 78 4ms 9 Apr 2024 857th dokutan 691 129 315ms 10 Mar 2025 858th voytxt 🇨🇿 690 64 15ms 21 Jul 2023 859th prplz 🇦🇺 685 113 30ms 31 Dec 2022 860th CaedenHarper 🇨🇦 685 130 244ms 3 Dec 2024 861st Anthony-Williams-06 684 74 17ms 12 Sep 2024 862nd steffan-polygolf 684 77 80ms 24 Feb 2023 863rd annaproxy 683 94 356ms 22 Oct 2023 864th janbehrens 🇩🇪 682 79 4ms 20 Nov 2022 864th weliveinhell 🇭🇹 682 79 4ms 21 May 2024 866th Yewzir 🇧🇪 681 73 40ms 24 Feb 2024 867th weliveinhell 🇭🇹 680 65 12ms 15 Sep 2023 867th dylanarmstrong 680 65 12ms 25 Jan 2024 867th Yewzir 🇧🇪 680 65 14ms 12 Feb 2024 870th Yewzir 🇧🇪 680 69 6ms 13 Feb 2024 871st snoozingnewt 🇨🇦 680 102 417ms 9 Oct 2025 872nd kkoenig 680 131 282ms 2 Jan 2024 873rd snoozingnewt 🇨🇦 679 52 4ms 9 Oct 2025 874th MeWhenI 🇻🇦 679 77 94ms 9 Apr 2024 875th MeWhenI 🇻🇦 679 92 45ms 14 Feb 2025 875th AlephSquirrel 679 92 48ms 21 Mar 2025 877th msbranicky 678 76 4,767ms 6 Jan 2025 878th AlephSquirrel 678 97 6ms 5 Aug 2024 879th angel-p57 🇯🇵 678 215 291ms 11 Dec 2023 880th MeWhenI 🇻🇦 678 245 448ms 19 Apr 2025 First Prev 801–880 of 1,816 Next Last