The Calendar hole will go live in approximately 8 days. Why not try and solve it ahead of time?
Collatz 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 146th m-tkach 🇺🇦 939 83 383ms 10 Apr 2025 146th DialFrost 🇸🇬 939 83 386ms 10 Apr 2025 146th Pecanolith 939 83 383ms 19 Apr 2025 146th Tyrant7 939 83 393ms 19 Apr 2025 146th Yax42 🇫🇷 939 83 381ms 19 Apr 2025 146th MeWhenI 🇻🇦 939 83 344ms 19 Jun 2025 146th sean-niemann 🇺🇸 939 83 346ms 20 Jun 2025 146th stefangimmillaro 939 83 389ms 20 Jun 2025 146th tomh1012 939 83 451ms 28 Aug 2025 146th fuzzylojik-golf 🇺🇸 939 83 363ms 8 Sep 2025 146th CaedenHarper 🇨🇦 939 83 357ms 17 Oct 2025 172nd grey0ut 937 48 2,043ms 8 Apr 2025 173rd GolfingSuccess 🇬🇷 937 49 38ms 12 Aug 2024 173rd Shanethegamer 🇺🇸 937 49 39ms 12 Aug 2024 173rd Steffan153 🇫🇮 937 49 39ms 12 Aug 2024 173rd MeWhenI 🇻🇦 937 49 37ms 13 Aug 2024 173rd DialFrost 🇸🇬 937 49 39ms 13 Aug 2024 173rd GrayJoKing 🇦🇺 937 49 41ms 15 Aug 2024 173rd btnlq 937 49 39ms 16 Aug 2024 173rd emgordon154 937 49 41ms 19 Aug 2024 173rd ovs-code 🇩🇪 937 49 39ms 19 Aug 2024 173rd mousetail 🇳🇱 937 49 42ms 13 Sep 2024 173rd lynn 937 49 40ms 20 Dec 2024 173rd weeble 937 49 40ms 20 Dec 2024 173rd sean-niemann 🇺🇸 937 49 40ms 11 Jan 2025 186th JayXon 🇺🇸 937 66 1,258ms 18 Nov 2025 187th DialFrost 🇸🇬 937 89 402ms 24 Sep 2025 187th ovs-code 🇩🇪 937 89 448ms 24 Sep 2025 187th dokutan 937 89 417ms 24 Sep 2025 187th sean-niemann 🇺🇸 937 89 456ms 24 Sep 2025 187th Shanethegamer 🇺🇸 937 89 438ms 25 Sep 2025 187th nwellnhof 🇩🇪 937 89 429ms 25 Sep 2025 187th m-tkach 🇺🇦 937 89 415ms 25 Sep 2025 187th namelessiw 937 89 456ms 2 Oct 2025 187th Yewzir 🇧🇪 937 89 695ms 2 Oct 2025 187th Yax42 🇫🇷 937 89 422ms 4 Oct 2025 187th stefangimmillaro 937 89 428ms 6 Oct 2025 187th CaedenHarper 🇨🇦 937 89 433ms 9 Oct 2025 187th Jacob385 937 89 452ms 27 Oct 2025 187th MeWhenI 🇻🇦 937 89 416ms 7 Nov 2025 187th ethanlally 937 89 433ms 10 Nov 2025 187th snoozingnewt 🇨🇦 937 89 394ms 23 Nov 2025 187th ScottHamper 937 89 436ms 22 days ago 187th KasperKivimaeki 🇫🇮 937 89 335ms 22 days ago 205th nwellnhof 🇩🇪 933 42 486ms 4 May 2022 205th Lydxn 🇨🇦 933 42 1,749ms 4 May 2022 205th GrayJoKing 🇦🇺 933 42 396ms 4 May 2022 205th Steffan153 🇫🇮 933 42 364ms 16 Dec 2022 205th sisyphus-ppcg 🇦🇺 933 42 400ms 31 Jan 2023 205th ovs-code 🇩🇪 933 42 423ms 30 Dec 2023 205th sean-niemann 🇺🇸 933 42 463ms 8 Mar 2025 212th emplv 🇱🇻 933 60 12ms 5 May 2022 212th GrayJoKing 🇦🇺 933 60 11ms 6 May 2022 212th targrik 933 60 13ms 24 Dec 2024 212th xsot 🇸🇬 933 60 12ms 1 May 2025 216th m-tkach 🇺🇦 932 91 64ms 5 May 2022 216th 09cf 932 91 81ms 4 Oct 2023 218th GrayJoKing 🇦🇺 931 56 411ms 15 Jan 2024 218th AlephSquirrel 931 56 426ms 21 Jan 2024 220th MeWhenI 🇻🇦 931 68 91ms 23 Feb 2023 220th JayXon 🇺🇸 931 68 88ms 4 Mar 2025 222nd ovs-code 🇩🇪 930 60 4ms 9 Oct 2023 222nd GrayJoKing 🇦🇺 930 60 4ms 11 Oct 2023 222nd Lydxn 🇨🇦 930 60 5ms 11 Oct 2023 222nd GolfingSuccess 🇬🇷 930 60 4ms 16 Nov 2023 222nd Steffan153 🇫🇮 930 60 5ms 28 Jan 2024 222nd JayXon 🇺🇸 930 60 5ms 29 Jan 2024 222nd rucin93 🇵🇱 930 60 5ms 10 Jul 2024 222nd sean-niemann 🇺🇸 930 60 5ms 10 Jul 2024 230th Lydxn 🇨🇦 930 70 106ms 17 Oct 2022 230th JayXon 🇺🇸 930 70 99ms 17 Oct 2022 232nd Natanaelel 🇸🇪 929 28 164ms 22 Jul 2022 232nd SirBogman 🇺🇸 929 28 173ms 17 Sep 2022 234th Steffan153 🇫🇮 929 67 37ms 19 Aug 2024 234th JayXon 🇺🇸 929 67 37ms 19 Aug 2024 236th sisyphus-ppcg 🇦🇺 928 50 2,414ms 31 Jan 2023 236th saito-ta 🇯🇵 928 50 759ms 12 Dec 2024 238th JayXon 🇺🇸 928 57 133ms 19 Aug 2024 239th sisyphus-ppcg 🇦🇺 928 65 106ms 4 days ago 239th ovs-code 🇩🇪 928 65 123ms 4 days ago First Prev 161–240 of 3,496 Next Last