The Calendar hole will go live in approximately 13 days. Why not try and solve it ahead of time?
Pernicious Numbers in Python 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 479th SniperSmiley 🇺🇸 476 84 9ms 13 Dec 2022 479th bwenstar 476 84 9ms 21 Feb 2024 483rd louisbosqui 471 85 9ms 29 Dec 2020 483rd timchu 471 85 9ms 3 Mar 2021 483rd olavaga 471 85 9ms 13 Aug 2021 483rd gitbedd 🇬🇧 471 85 9ms 11 Jan 2022 483rd PaulMWeiser 471 85 9ms 4 Mar 2023 483rd NoneTheFewer 471 85 10ms 18 May 2024 489th qoqosz 465 86 9ms 6 Jun 2019 489th tomh1012 465 86 15ms 9 Jun 2021 489th JoaoFelipe3 465 86 16ms 15 Jan 2024 489th Pale-Vessel 465 86 15ms 18 May 2024 489th 0dyse 465 86 17ms 26 Sep 2025 494th alangodfrey 460 87 11ms 24 Jan 2019 494th TheZwierzLF 🇵🇱 460 87 16ms 26 May 2025 494th SectorCorruptor 460 87 9ms 25 Sep 2025 497th richard-oelze 🇩🇪 455 88 9ms 10 Feb 2021 498th dave-ck 449 89 9ms 9 May 2018 498th TheCod-r 🇦🇶 449 89 9ms 4 Mar 2022 498th Techdude01 449 89 16ms 19 Dec 2022 498th DanielPeterssonAI 449 89 9ms 18 Mar 2023 498th Short-C0de 🇺🇸 449 89 9ms 14 Nov 2024 503rd Secozzi 444 90 10ms 21 Mar 2021 503rd potato-jackson 444 90 9ms 9 Sep 2021 503rd pengu1n-master 444 90 9ms 11 Oct 2021 503rd feherd 444 90 9ms 20 May 2022 503rd ssbhatt4321 444 90 9ms 14 Oct 2023 503rd webmiche 444 90 10ms 6 Nov 2025 509th karhuthebear 440 91 10ms 11 May 2022 509th mdnestor 440 91 9ms 23 Dec 2022 509th AstroOrbis 440 91 16ms 16 Jul 2025 512th jamesbtan 435 92 10ms 25 Mar 2019 512th Bonjour27891 🇻🇳 435 92 16ms 19 Feb 2022 512th Drew-j-Smith 435 92 9ms 17 Apr 2022 512th jaxmattfair 🇺🇸 435 92 10ms 17 Jan 2023 512th shellbertt 🇨🇦 435 92 9ms 26 Feb 2023 512th Bit125 435 92 10ms 28 Mar 2024 518th DarkTemplar5 430 93 10ms 1 Nov 2020 518th bbakersmith 430 93 10ms 18 Jul 2021 518th j-Ewan 430 93 16ms 11 Mar 2022 518th cameronezell 430 93 9ms 19 Jun 2022 518th TheAtrossian 430 93 10ms 17 days ago 523rd try-except-try-accept 🇹🇭 426 94 15ms 10 Jul 2022 523rd madeforlosers 426 94 9ms 11 Nov 2025 525th opsullivan85 421 95 9ms 3 Jun 2019 525th bdendekk 421 95 9ms 10 Jul 2019 525th Trunksistor 🇫🇷 421 95 15ms 20 May 2022 525th Heathcorp 🇦🇺 421 95 15ms 24 Jun 2022 525th pfysches-boop 421 95 9ms 6 Aug 2023 525th madex 🇩🇪 421 95 15ms 9 Jul 2024 531st OpesMentis 417 96 9ms 21 Mar 2018 531st Y0UR-U5ERNAME 417 96 13ms 5 Sep 2021 531st myleopard 417 96 9ms 15 Oct 2021 531st JesseNoEyes 🇺🇸 417 96 16ms 20 Oct 2024 535th adoxography 412 97 17ms 10 Oct 2019 535th twocatsinatrenchcoat 412 97 9ms 11 May 2022 537th AgathokakologicalBit 408 98 17ms 25 Jul 2019 537th eshilo-draper 408 98 9ms 13 Sep 2022 537th Florian-Mt 408 98 15ms 2 Oct 2023 537th Ythaenagor 408 98 9ms 5 Aug 2024 537th arjunarya1 408 98 9ms 11 Sep 2025 542nd derekthatcher 404 99 15ms 23 Sep 2020 542nd garrisonhh 404 99 15ms 21 Nov 2020 542nd midnattssol 🇸🇪 404 99 9ms 27 Jul 2023 545th berdzi 400 100 14ms 23 Mar 2022 546th dillon-duncando 396 101 15ms 3 Oct 2022 547th ArturLange 392 102 16ms 5 Sep 2018 547th evautier 392 102 9ms 15 May 2019 547th ItsMeNoobieboy 392 102 10ms 23 Dec 2022 547th stegosaurus21 392 102 9ms 29 Aug 2023 547th jameswmccarty 392 102 16ms 7 Mar 2025 552nd stordev 388 103 15ms 26 Feb 2021 552nd mhenion8293 🇺🇸 388 103 15ms 19 Jan 2022 554th S-Ruban 385 104 9ms 25 Feb 2023 555th bkshrader 381 105 9ms 29 Dec 2018 555th danwley 381 105 9ms 5 Jan 2019 555th rpuneet 381 105 9ms 27 Sep 2019 555th Pena86 381 105 17ms 18 Feb 2021 559th TetroVolt 377 106 9ms 10 Sep 2018 559th hymanimy 377 106 9ms 6 Jun 2021 First Prev 481–560 of 648 Next Last