The Calendar hole will go live in approximately 7 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 641st pardouin 🇫🇷 788 68 57ms 25 Apr 2025 642nd stefangimmillaro 788 113 268ms 22 Jun 2023 643rd Steffan153 🇫🇮 787 75 49ms 22 Aug 2024 644th sisyphus-ppcg 🇦🇺 785 45 13ms 23 Jan 2023 644th Steffan153 🇫🇮 785 45 4ms 9 Feb 2023 644th DialFrost 🇸🇬 785 45 4ms 25 Nov 2023 647th Yewzir 🇧🇪 783 43 903ms 13 Feb 2024 647th dokutan 783 43 981ms 30 Apr 2024 649th Steffan153 🇫🇮 783 84 6ms 16 Jul 2023 649th typeswitch-dev 🇵🇹 783 84 398ms 28 Jul 2023 649th GrayJoKing 🇦🇺 783 84 375ms 29 Jul 2023 652nd targrik 782 60 9ms 16 Jan 2025 653rd pardouin 🇫🇷 782 79 187ms 22 Apr 2025 654th inventshah 781 69 5ms 29 Nov 2022 654th xsot 🇸🇬 781 69 4ms 10 Feb 2024 654th ovs-code 🇩🇪 781 69 5ms 10 Feb 2024 657th emgordon154 781 106 115ms 25 days ago 658th SirBogman 🇺🇸 780 33 332ms 22 Nov 2022 659th fourth-bit 779 65 19ms 11 Jul 2023 659th Bmrl7 779 65 18ms 24 Feb 2024 659th shelerr 779 65 26ms 22 Aug 2025 662nd prplz 🇦🇺 778 41 235ms 19 Nov 2022 662nd scpchicken 🇵🇼 778 41 222ms 20 Nov 2022 662nd SirFireball3521 778 41 245ms 13 Mar 2023 665th Steffan153 🇫🇮 778 72 98ms 20 Nov 2022 665th emplv 🇱🇻 778 72 100ms 30 Nov 2022 667th albanian-laundromat 776 55 774ms 12 Sep 2025 668th Yewzir 🇧🇪 776 88 25ms 13 Feb 2024 669th Steffan153 🇫🇮 775 57 12ms 14 Jan 2023 669th sisyphus-ppcg 🇦🇺 775 57 11ms 20 Jul 2023 671st rak1507 🇬🇧 774 31 2ms 7 Jan 2023 671st Yewzir 🇧🇪 774 31 9ms 9 Dec 2023 671st snoozingnewt 🇨🇦 774 31 37ms 20 Sep 2025 674th DialFrost 🇸🇬 773 181 52ms 23 May 2025 675th xsot 🇸🇬 772 50 54ms 30 Jan 2024 676th pardouin 🇫🇷 772 76 10ms 24 Apr 2025 677th DialFrost 🇸🇬 772 80 184ms 5 Aug 2024 678th dokutan 771 95 60ms 23 Mar 2024 679th Yewzir 🇧🇪 770 90 435ms 12 Feb 2024 680th emplv 🇱🇻 769 61 8ms 21 Jun 2023 681st Yewzir 🇧🇪 769 68 123ms 14 Feb 2024 682nd janbehrens 🇩🇪 768 116 274ms 20 Nov 2022 683rd aksyristos 767 66 19ms 17 Jan 2023 683rd OllieBoyne 🇬🇧 767 66 19ms 28 Feb 2023 683rd randolchance 767 66 19ms 12 Mar 2023 683rd CheeseCake628 🇳🇴 767 66 18ms 19 Mar 2023 683rd adamnielson42 🇺🇸 767 66 17ms 31 Mar 2023 683rd ehulinsky 🇺🇸 767 66 18ms 8 May 2023 683rd TheoKeller1 767 66 17ms 11 Jun 2023 683rd dranjohn 767 66 16ms 11 Sep 2023 683rd inverseLorentz 🇦🇺 767 66 19ms 23 Oct 2023 683rd RedzGoose 🇦🇺 767 66 19ms 23 Oct 2024 683rd yokasuretsu 767 66 17ms 7 Jan 2025 683rd croc54 767 66 17ms 13 Jan 2025 683rd ejini6969 767 66 17ms 14 Jun 2025 683rd osNiko 🇧🇷 767 66 17ms 20 Aug 2025 683rd Troon 767 66 24ms 22 Aug 2025 698th Kaffeleif 767 71 24ms 8 Feb 2024 698th DialFrost 🇸🇬 767 71 24ms 15 Dec 2024 698th snoozingnewt 🇨🇦 767 71 28ms 9 Oct 2025 701st Irratix 🇳🇱 763 96 57ms 11 Dec 2022 702nd AlephSquirrel 762 58 116ms 1 Jun 2023 703rd JGDoerrer 761 90 125ms 20 Dec 2022 703rd klixel 🇨🇦 761 90 124ms 17 Apr 2023 703rd TylerBloom 761 90 118ms 22 Mar 2024 703rd Aurel300 🇨🇭 761 90 119ms 8 Jun 2024 707th ovs-code 🇩🇪 759 70 23ms 14 Dec 2024 708th lynn 759 102 31ms 18 Jul 2023 708th m-tkach 🇺🇦 759 102 31ms 7 Dec 2023 710th DialFrost 🇸🇬 758 69 115ms 5 days ago 711th tigerdan2 🇩🇪 758 92 450ms 24 days ago 712th SirBogman 🇺🇸 756 41 332ms 9 Jan 2024 712th dcgjb 756 41 1,753ms 31 Jan 2024 712th IISResetMe 756 41 313ms 10 Apr 2024 712th juliansiebert 🇩🇪 756 41 326ms 2 Feb 2025 716th snoozingnewt 🇨🇦 756 55 254ms 9 Oct 2025 717th bob-th 755 67 17ms 23 Dec 2022 717th n0Oo0Oo0b 755 67 18ms 29 Dec 2022 717th betaveros 755 67 32ms 31 Dec 2022 717th vgamula 🇺🇦 755 67 17ms 15 Mar 2023 First Prev 641–720 of 1,817 Next Last