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 481st emplv 🇱🇻 853 80 24ms 30 Nov 2022 482nd Steffan153 🇫🇮 852 86 59ms 14 Jan 2023 482nd tailorspy 852 86 65ms 24 May 2024 482nd snyderek 🇺🇸 852 86 57ms 13 Oct 2024 485th MeWhenI 🇻🇦 851 64 23ms 12 Dec 2023 485th emgordon154 851 64 23ms 10 Dec 2024 487th kg583 🇺🇸 850 63 49ms 26 Aug 2025 488th primo-ppcg 🇹🇭 849 62 82ms 20 Nov 2022 489th Shanethegamer 🇺🇸 848 49 538ms 10 Dec 2023 490th Yewzir 🇧🇪 846 56 379ms 24 Feb 2024 491st MeWhenI 🇻🇦 846 68 85ms 24 Dec 2024 492nd GrayJoKing 🇦🇺 845 73 44ms 26 Oct 2023 493rd Shanethegamer 🇺🇸 845 82 389ms 21 Nov 2022 494th ovs-code 🇩🇪 845 149 509ms 27 Mar 2025 495th primo-ppcg 🇹🇭 844 135 1,735ms 15 Sep 2025 496th janbehrens 🇩🇪 843 60 24ms 20 Nov 2022 496th Omega65536 🇩🇪 843 60 17ms 24 Nov 2022 496th Just4FunCoder 843 60 16ms 24 Mar 2023 496th Fracture17 843 60 19ms 13 Apr 2023 496th GolfingSuccess 🇬🇷 843 60 18ms 17 Oct 2023 496th steffan-polygolf 843 60 18ms 14 Feb 2024 496th bzijlema 🇳🇱 843 60 29ms 22 Jul 2024 496th bizy-coder 843 60 18ms 15 Aug 2024 496th keelimeguy 🇺🇸 843 60 19ms 15 May 2025 505th DialFrost 🇸🇬 843 81 24ms 23 Dec 2024 505th fuzzylojik-golf 🇺🇸 843 81 24ms 20 Aug 2025 507th DialFrost 🇸🇬 842 57 95ms 18 hours ago 508th m-tkach 🇺🇦 842 87 87ms 22 Nov 2022 508th sean-niemann 🇺🇸 842 87 70ms 7 Feb 2023 510th GrayJoKing 🇦🇺 842 92 28ms 26 Oct 2023 511th dokutan 840 49 54ms 30 Apr 2024 512th MeWhenI 🇻🇦 837 51 707ms 15 Sep 2025 512th dokutan 837 51 676ms 16 days ago 514th Steffan153 🇫🇮 837 56 28ms 9 Feb 2023 514th sean-niemann 🇺🇸 837 56 26ms 2 Aug 2024 516th MeWhenI 🇻🇦 837 64 52ms 9 Apr 2024 517th ovs-code 🇩🇪 835 74 332ms 12 Nov 2023 518th janbehrens 🇩🇪 835 83 420ms 20 Nov 2022 519th duckyluuk 🇳🇱 833 69 93ms 25 Dec 2024 520th Steffan153 🇫🇮 833 75 49ms 22 Aug 2024 521st Yax42 🇫🇷 833 77 458ms 21 Apr 2025 522nd primo-ppcg 🇹🇭 833 82 25ms 20 Nov 2022 523rd janbehrens 🇩🇪 831 50 500ms 11 Jul 2023 524th dokutan 831 57 361ms 7 Apr 2024 525th emgordon154 831 62 4,090ms 8 Nov 2024 526th lynn 830 31 138ms 16 Oct 2023 527th Eilonlif 🇮🇱 830 61 17ms 9 Dec 2022 527th SirFireball3521 830 61 16ms 9 Mar 2023 527th minhtrancccp 830 61 19ms 11 Jan 2024 527th stertooy 🇧🇪 830 61 17ms 14 Jun 2024 531st SirBogman 🇺🇸 829 60 41ms 9 Jan 2024 532nd GolfingSuccess 🇬🇷 828 29 3ms 25 Feb 2023 532nd 5cw 🇺🇸 828 29 5ms 10 Apr 2023 532nd codereport 🇨🇦 828 29 3ms 17 May 2024 535th snoozingnewt 🇨🇦 828 100 120ms 20 days ago 536th Ripick 827 69 155ms 8 Jan 2023 536th dokutan 827 69 155ms 31 Dec 2023 536th Yewzir 🇧🇪 827 69 168ms 14 Feb 2024 539th AlephSquirrel 823 50 42ms 7 Mar 2023 539th SirBogman 🇺🇸 823 50 55ms 10 Jan 2024 541st jared-hughes 823 89 57ms 20 Nov 2022 541st roupiq 🇵🇱 823 89 73ms 3 Jan 2024 541st Herbert00709 🇵🇱 823 89 75ms 7 Jun 2024 541st DialFrost 🇸🇬 823 89 64ms 17 Jun 2024 541st KasperKivimaeki 🇫🇮 823 89 60ms 12 days ago 546th DialFrost 🇸🇬 820 139 1,670ms 13 Sep 2025 547th KatieLG 🇬🇧 816 62 16ms 26 Nov 2022 547th suwat513 816 62 17ms 6 Dec 2022 547th StefanHabel 🇨🇦 816 62 19ms 19 Dec 2022 547th Ripick 816 62 23ms 1 Feb 2023 547th quimey 816 62 17ms 8 Mar 2023 547th firegene 🇮🇪 816 62 16ms 2 Apr 2023 547th yzhs 🇩🇪 816 62 23ms 23 Jun 2023 547th Andriamanitra 🇫🇮 816 62 17ms 17 Jul 2023 547th Re-Adventures 🇮🇳 816 62 18ms 20 Jul 2023 547th fkantelberg 816 62 17ms 12 Aug 2023 547th Mikey-Beep 🇬🇧 816 62 16ms 23 Aug 2023 547th htareque 816 62 16ms 13 Oct 2023 547th neel11235813 816 62 17ms 27 Mar 2024 547th SB-945 816 62 18ms 31 Mar 2024 First Prev 481–560 of 1,816 Next Last