The Calendar hole will go live in approximately 10 days. Why not try and solve it ahead of time?
Pernicious Numbers in Python 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 319th Pyroan 690 58 15ms 7 Nov 2022 319th Hortaros 690 58 15ms 21 Apr 2023 319th Mr-McChicken 690 58 9ms 4 Oct 2025 324th lmeuser 678 59 9ms 2 Dec 2017 324th adamhass 678 59 11ms 19 Jul 2018 324th shibacho 🇯🇵 678 59 9ms 17 Apr 2019 324th estomagordo 🇳🇱 678 59 9ms 3 Aug 2019 324th giacomogallina 678 59 10ms 4 Oct 2019 324th TheAristos 678 59 8ms 16 Oct 2019 324th anominos 678 59 9ms 14 Dec 2019 324th bastienvoirin 🇫🇷 678 59 10ms 8 Apr 2020 324th guliyevemil1 🇦🇿 678 59 9ms 21 Apr 2020 324th mcdowell95 678 59 9ms 23 Apr 2020 324th DarkBlueWall 678 59 9ms 29 Apr 2020 324th rowboat1 678 59 9ms 29 May 2020 324th Vaekor 678 59 9ms 16 Nov 2020 324th OwenElliottDev 678 59 9ms 16 Feb 2021 324th josephjojoe 678 59 9ms 23 Feb 2021 324th asadullayev 678 59 9ms 3 Mar 2021 324th jhunterkohler 678 59 9ms 19 May 2021 324th ethandhunt 678 59 9ms 15 Aug 2021 324th mauro-1 🇮🇹 678 59 10ms 18 Aug 2021 324th MichalMarsalek 🇨🇿 678 59 9ms 3 Dec 2021 324th HumanEquivalentUnit 678 59 9ms 28 Dec 2021 324th krcs 🇵🇱 678 59 9ms 3 May 2022 324th glesnick 678 59 9ms 19 Sep 2022 324th jakobkordez 🇸🇮 678 59 16ms 21 Nov 2022 324th eiburns 678 59 9ms 21 Jan 2023 324th Skwerl23 678 59 9ms 5 Feb 2023 324th geooff 678 59 9ms 3 Jul 2023 324th epic-programmer-guy 678 59 9ms 20 Dec 2023 324th CutSandstone 678 59 9ms 5 Jul 2024 324th Emutis 🇱🇹 678 59 9ms 4 Aug 2025 324th Code-Coder-coder 678 59 9ms 11 Oct 2025 324th Andrey2001 678 59 10ms 12 days ago 356th lrustand 667 60 9ms 15 Jan 2018 356th jiaminglimjm 🇲🇾 667 60 9ms 27 Nov 2019 356th martinnorling 🇸🇪 667 60 10ms 1 Feb 2022 356th juliusgeo 667 60 9ms 12 Jan 2023 356th vgledel 667 60 9ms 30 Oct 2023 356th RobertHoeh 667 60 15ms 6 Dec 2023 356th hellwue 667 60 17ms 25 Jun 2024 363rd msrawson 656 61 9ms 4 Sep 2018 363rd benwilliamgraham 656 61 10ms 28 Feb 2019 363rd elldur 656 61 9ms 17 Mar 2019 363rd sambirnbaum1 656 61 9ms 13 Oct 2019 363rd theonlytruemathnerd 656 61 9ms 10 Jan 2020 363rd oAsAo 656 61 9ms 21 Jan 2020 363rd mortimervonchappuis 656 61 10ms 17 Mar 2020 363rd achow0 656 61 12ms 5 Aug 2020 363rd jameslindesay 656 61 9ms 18 Aug 2020 363rd boxjelly 656 61 9ms 8 Feb 2021 363rd NoahBolohan 🇨🇦 656 61 9ms 8 Feb 2023 363rd CatsAreFluffy 656 61 9ms 20 Feb 2023 363rd mbittner20 656 61 9ms 27 May 2023 363rd LiquidPulsar 656 61 9ms 19 Jul 2023 363rd Clay-Goodling 656 61 9ms 8 Oct 2024 363rd Artemis21 🇬🇧 656 61 10ms 31 Dec 2024 363rd WillowWispy 656 61 9ms 14 Mar 2025 380th relet 645 62 10ms 10 Aug 2018 380th jotslo 🇬🇧 645 62 9ms 14 Jul 2019 380th cellobix 645 62 17ms 14 Aug 2019 380th artieleach 645 62 9ms 8 Feb 2021 380th befoster 645 62 9ms 10 Apr 2021 380th fynnkroeger 645 62 9ms 30 Jan 2022 380th Schmitz48 645 62 9ms 11 May 2022 387th kypi 635 63 9ms 22 Feb 2020 387th ArmaanAS 635 63 9ms 8 Mar 2021 387th Andrey135296 635 63 9ms 25 Oct 2022 387th Anthony-Williams-06 635 63 9ms 12 Sep 2024 387th ffelixm 635 63 9ms 12 Jun 2025 392nd GodEmperorCaterpie 625 64 9ms 31 Aug 2019 392nd amishtal 625 64 10ms 30 Nov 2019 392nd wrhm 625 64 9ms 12 Dec 2020 392nd samgiz 625 64 9ms 30 Oct 2021 392nd hippopotam00sehead 🇨🇦 625 64 10ms 13 Sep 2024 397th willzywiec 615 65 9ms 6 Aug 2018 397th hoodadam 615 65 9ms 30 Aug 2019 397th brian6liu 615 65 9ms 8 May 2020 397th Altrul 615 65 10ms 17 Dec 2020 First Prev 321–400 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