The Calendar hole will go live in approximately 13 days. Why not try and solve it ahead of time?
Niven 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 639th kusti8 667 66 9ms 30 Jul 2019 639th GodEmperorCaterpie 667 66 9ms 4 Sep 2019 639th KiwiKoder0123 667 66 9ms 22 Oct 2019 639th DarkTemplar5 667 66 15ms 24 Feb 2020 639th jthomas1294 667 66 9ms 7 May 2020 639th VictorFordham 667 66 10ms 8 Aug 2020 639th the-soph-ia 667 66 9ms 31 Jan 2021 639th ethandhunt 667 66 9ms 21 Jul 2021 639th Y0UR-U5ERNAME 667 66 10ms 5 Sep 2021 639th martinnorling 🇸🇪 667 66 9ms 4 Feb 2022 639th Trunksistor 🇫🇷 667 66 9ms 18 May 2022 639th rowboat1 667 66 15ms 19 Jun 2022 639th Yareeeema 667 66 10ms 6 Jan 2023 639th Skwerl23 667 66 9ms 6 Feb 2023 639th Azearia 667 66 10ms 13 Aug 2023 639th tails618 667 66 9ms 21 Aug 2023 639th ItsEthanXYZ 667 66 9ms 13 Dec 2023 639th jmjaggi1202 667 66 9ms 13 Dec 2023 639th SectorCorruptor 667 66 10ms 27 Jan 2024 639th Ralac07 🇦🇺 667 66 10ms 12 Jun 2024 639th JesseNoEyes 🇺🇸 667 66 10ms 12 Oct 2024 639th Alex-Huggett 🇬🇧 667 66 15ms 23 Oct 2024 639th munchsaga 667 66 10ms 12 Jan 2025 639th CodyKlingler 667 66 9ms 7 Feb 2025 639th 6t41m0ct5 667 66 9ms 14 Apr 2025 639th Upload-and-View 🇺🇦 667 66 12ms 26 Aug 2025 639th lokeshllkumar 667 66 9ms 26 Sep 2025 668th mvrkws 657 67 9ms 5 Dec 2018 668th zuparnowa 657 67 9ms 23 Jan 2019 668th Edgex42 657 67 9ms 25 May 2019 668th usnheckler 657 67 10ms 7 Jun 2019 668th henrytranter 657 67 9ms 20 Sep 2019 668th simplylu 657 67 9ms 5 Jun 2020 668th Psirving 657 67 9ms 21 Jul 2020 668th PyPylia 🇦🇺 657 67 9ms 7 Aug 2020 668th jameslindesay 657 67 9ms 24 Feb 2021 668th Larspolo 657 67 9ms 6 Jun 2021 668th feherd 657 67 9ms 29 Aug 2021 668th charlieharutaka 657 67 9ms 28 Sep 2021 668th sbr075 657 67 9ms 7 Dec 2021 668th brochmann 🇸🇪 657 67 9ms 7 Feb 2022 668th Marco-perce 657 67 10ms 12 Aug 2022 668th TimLeffke 657 67 9ms 17 Aug 2022 668th mdnestor 657 67 9ms 27 Dec 2022 668th Pimveha 657 67 9ms 12 Jan 2023 668th UriyaBA 657 67 10ms 20 Mar 2023 668th A-Dummo 657 67 9ms 28 May 2023 668th Fanrco 657 67 9ms 31 Aug 2023 668th epic-programmer-guy 657 67 9ms 20 Dec 2023 668th ComputerKWasTaken 🇺🇸 657 67 15ms 1 Jun 2024 668th lhulinsky 657 67 10ms 21 Oct 2024 668th Naitzirch 🇳🇱 657 67 10ms 3 Jul 2025 668th TJK-S 657 67 9ms 22 Oct 2025 694th Visckmart 647 68 9ms 22 Jul 2018 694th mfinzi 647 68 9ms 19 Nov 2018 694th EmadAIsmael 647 68 9ms 22 Jan 2019 694th jrburga 647 68 9ms 17 Nov 2019 694th scottJsonar 647 68 9ms 29 Nov 2019 694th Malin001 647 68 9ms 4 Jan 2020 694th theonlytruemathnerd 647 68 9ms 10 Jan 2020 694th mcdowell95 647 68 9ms 1 Apr 2020 694th havardMoe 647 68 9ms 30 Jul 2020 694th achow0 647 68 9ms 3 Aug 2020 694th potato-jackson 647 68 9ms 1 Mar 2021 694th peculiarination 647 68 10ms 20 May 2021 694th orifu 647 68 9ms 25 Jun 2021 694th twocatsinatrenchcoat 647 68 10ms 14 Apr 2022 694th Shiran-Yuan 647 68 9ms 5 Apr 2023 694th SURAJMITTAL 647 68 9ms 19 Dec 2024 694th WillowWispy 647 68 9ms 15 Mar 2025 694th SOONwasTaken 647 68 9ms 19 Mar 2025 694th saturzay 647 68 9ms 22 Aug 2025 694th EthanJantz 647 68 10ms 22 Aug 2025 694th therealnumbers 647 68 9ms 26 Sep 2025 694th Yash-Sangtani 647 68 9ms 5 Oct 2025 716th willzywiec 638 69 9ms 6 Aug 2018 716th SimonPeatman 638 69 9ms 28 Dec 2018 716th YH-Kang 638 69 9ms 1 Feb 2019 716th toabi 638 69 9ms 21 Aug 2019 716th austinrwarner 638 69 9ms 12 Sep 2019 First Prev 641–720 of 909 Next Last