The Calendar hole will go live in approximately 9 days. Why not try and solve it ahead of time?
Collatz in all languages 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 Lydxn 🇨🇦 892 50 404ms 15 Aug 2022 479th Steffan153 🇫🇮 892 50 408ms 9 Aug 2024 483rd Lydxn 🇨🇦 892 72 353ms 16 Jul 2023 484th edsrzf 🇳🇿 892 78 11ms 26 Oct 2024 484th kg583 🇺🇸 892 78 12ms 25 Sep 2025 486th MichalMarsalek 🇨🇿 892 87 366ms 5 May 2022 486th Kloppermand 🇩🇰 892 87 375ms 7 Oct 2022 486th bwat2 892 87 348ms 6 Apr 2023 489th GrayJoKing 🇦🇺 892 91 29ms 19 Jan 2023 490th Ripick 891 73 133ms 8 May 2023 491st oeb25 891 93 120ms 16 May 2022 491st snobee 🇨🇦 891 93 119ms 8 Dec 2022 491st logvp 891 93 120ms 2 Jan 2024 491st elgan65536 891 93 120ms 5 Mar 2024 491st smartiel 891 93 124ms 12 Aug 2024 491st trist224 🇫🇷 891 93 122ms 12 Aug 2024 491st nullie 891 93 119ms 19 Dec 2024 491st lolgeny 891 93 116ms 22 Feb 2025 499th p-zubieta 890 48 316ms 6 Mar 2024 500th Steffan153 🇫🇮 890 80 24ms 11 Dec 2023 501st GolfingSuccess 🇬🇷 890 95 74ms 5 May 2022 501st Alex-x90 🇺🇸 890 95 57ms 4 Dec 2022 501st Mandrzejy 🇵🇱 890 95 67ms 22 Mar 2024 504th m-tkach 🇺🇦 890 117 25ms 7 May 2022 504th Lydxn 🇨🇦 890 117 26ms 7 May 2022 506th Steffan153 🇫🇮 889 80 26ms 15 Nov 2022 506th error256 889 80 115ms 8 Apr 2025 508th KatieLG 🇬🇧 888 60 10ms 4 May 2022 508th ScottHamper 888 60 10ms 5 May 2022 508th Re-Adventures 🇮🇳 888 60 10ms 5 May 2022 508th 0x24a537r9 888 60 10ms 29 Jul 2022 508th stefangabos 🇷🇴 888 60 10ms 19 Aug 2022 508th eranws 888 60 10ms 10 Sep 2022 508th GeorgeStechman 🇬🇧 888 60 10ms 26 Sep 2022 508th BloodStormKnight 888 60 10ms 15 Oct 2022 508th dzshn 888 60 10ms 3 Dec 2022 508th biocommando 🇫🇮 888 60 10ms 20 Dec 2022 508th Betuaredead 888 60 9ms 5 Jan 2023 508th piano-miles 888 60 9ms 16 Jan 2023 508th Yewzir 🇧🇪 888 60 10ms 12 Feb 2023 508th shellbertt 🇨🇦 888 60 10ms 26 Feb 2023 508th zakariamouhid 888 60 10ms 20 May 2023 508th raphaelimahorn 888 60 10ms 23 Aug 2023 508th jbt 888 60 9ms 25 Dec 2023 508th olleicua 🇺🇸 888 60 10ms 15 Feb 2024 508th HumanoidCPU 888 60 10ms 3 May 2024 508th dokutan 888 60 10ms 13 Aug 2024 508th LostSyntax21 🇬🇧 888 60 11ms 10 Sep 2024 508th xyangst 888 60 10ms 28 Sep 2024 508th a6166231 🇨🇳 888 60 9ms 15 May 2025 508th Protothor 888 60 10ms 8 Jul 2025 508th SebassNoob 888 60 10ms 5 Aug 2025 508th Yax42 🇫🇷 888 60 10ms 5 Sep 2025 508th levinwinter 888 60 10ms 22 Oct 2025 508th Cube14yt 888 60 10ms 16 Nov 2025 508th gigaprofisi 🇺🇸 888 60 10ms 17 Nov 2025 508th amazingalek 888 60 16ms 2 days ago 538th Lydxn 🇨🇦 888 107 263ms 6 May 2022 538th CaedenHarper 🇨🇦 888 107 308ms 5 Oct 2025 540th Shanethegamer 🇺🇸 887 61 5ms 31 Oct 2022 540th MeWhenI 🇻🇦 887 61 5ms 4 Nov 2022 542nd P-Quentin 🇫🇷 887 63 18ms 3 Aug 2022 542nd kaptsanovb 887 63 28ms 20 Apr 2023 542nd fkantelberg 887 63 20ms 14 Jul 2023 542nd VictorStenvers 🇳🇱 887 63 22ms 13 Nov 2023 542nd 1231234md5 🇨🇳 887 63 18ms 14 Dec 2023 542nd f-tucker 887 63 23ms 6 Feb 2024 542nd JunkIce 887 63 23ms 24 Nov 2024 542nd Kowalskiexe 🇵🇱 887 63 19ms 19 Apr 2025 542nd 123mjb 887 63 23ms 2 Jun 2025 542nd DrakeSeteraO 887 63 52ms 24 Oct 2025 542nd enigma 887 63 40ms 34 hours ago 553rd RockOfStone 887 73 4ms 20 Oct 2025 554th JayXon 🇺🇸 887 74 4,306ms 14 Nov 2024 555th jared-hughes 887 130 23ms 15 Dec 2024 556th canissimia 🇦🇶 887 204 16ms 25 Nov 2023 557th lynn 886 65 283ms 5 May 2022 557th GrayJoKing 🇦🇺 886 65 250ms 5 May 2022 557th Sakisan 🇧🇪 886 65 178ms 6 May 2022 557th JayXon 🇺🇸 886 65 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