The Calendar hole will go live in approximately 10 days. Why not try and solve it ahead of time?
Collatz 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 721st phpboyscout 589 107 16ms 18 May 2023 721st DrPrettyman 589 107 15ms 5 Jul 2023 721st joseph-w0ng 589 107 14ms 5 Jul 2024 721st EnisEfe0 589 107 24ms 18 May 2025 725th landyrisbad 583 108 20ms 13 Nov 2022 725th cakular 583 108 27ms 17 May 2024 725th glassala 583 108 16ms 25 Oct 2024 725th CarterStroik 583 108 19ms 12 Nov 2025 729th tjefferson401 578 109 27ms 16 Sep 2022 729th ariesmarinus 578 109 17ms 21 Nov 2024 731st profJGermain 573 110 19ms 7 Feb 2024 731st JMMMMC 573 110 20ms 23 Oct 2024 731st jtb0362 573 110 19ms 10 May 2025 734th sagnik3 563 112 18ms 8 Aug 2022 734th craftablescience 563 112 17ms 19 Sep 2023 736th kelseychristensen 558 113 19ms 2 Nov 2022 736th ArmsTheLimited 558 113 14ms 1 Jun 2023 738th HunterC14 553 114 26ms 18 Oct 2024 739th jstechman 548 115 20ms 24 Feb 2024 739th dan422442 548 115 19ms 19 Oct 2024 741st keelanfh 543 116 16ms 20 Dec 2023 741st returnitynet 543 116 16ms 27 Jan 2025 741st EthanPatel01000101 543 116 16ms 20 Oct 2025 744th gioto64 538 117 16ms 8 Dec 2022 744th WilfredSalmon 538 117 16ms 21 Oct 2023 746th XianchengZ 534 118 18ms 18 Aug 2023 746th brindak2005 534 118 16ms 2 May 2025 748th jmmographer 516 122 22ms 21 Oct 2023 748th RucatJ 516 122 17ms 8 Aug 2025 750th xbxbxb007 512 123 21ms 10 Jan 2024 751st kevinnaviapaiva 488 129 17ms 20 Feb 2025 752nd AdrianN001 485 130 17ms 6 Aug 2023 753rd wyatt-the-hump 481 131 15ms 24 Dec 2022 753rd hotmanga 481 131 13ms 20 Oct 2023 753rd Jordynar02 481 131 16ms 3 May 2025 756th Zach10za 474 133 22ms 23 Jan 2024 757th vtilde 470 134 17ms 8 Jan 2024 758th fig-apple 467 135 11ms 24 Jun 2023 759th S-Ruban 460 137 12ms 25 Feb 2023 760th FLOKI0421 453 139 16ms 4 May 2025 760th noahdorsch 453 139 18ms 5 May 2025 762nd bartsowka2000 423 149 20ms 10 Jul 2023 763rd KapelMeister 420 150 13ms 5 Sep 2025 764th sa1640 409 154 15ms 28 Apr 2025 765th arinhyther 406 155 16ms 24 Dec 2022 766th SebbeCaliban 401 157 17ms 11 Apr 2023 767th codefeld 364 173 18ms 5 Mar 2023 768th fl3ur1nestimable 354 178 15ms 24 Oct 2022 769th Laellekoenig 339 186 15ms 7 Nov 2025 770th Siyasia 333 189 16ms 22 Apr 2025 771st kalehika1234 326 193 13ms 24 Apr 2025 772nd hannahherbig 325 194 13ms 30 Mar 2023 773rd dahappy1989 307 205 17ms 5 Nov 2023 774th sahilshresthaa 306 206 13ms 4 May 2025 775th jalbertgordon 304 207 13ms 24 Oct 2023 776th AidanWalter 301 209 14ms 3 Jan 2025 777th sayloren 290 217 19ms 5 Mar 2023 777th AshayP123 290 217 17ms 1 May 2025 779th rubenguajardount 280 225 21ms 4 May 2025 780th amritm55 276 228 14ms 1 Apr 2025 781st clarkatunt19 275 229 21ms 3 May 2025 782nd jac1107 274 230 13ms 4 May 2025 782nd rcs0252 274 230 15ms 4 May 2025 784th apurbapokharel 269 234 21ms 3 Apr 2025 785th wlopez44 260 242 13ms 29 Apr 2025 785th sakshiPatel2602 260 242 14ms 3 May 2025 787th Zok030 259 243 14ms 1 Apr 2025 787th Josemnz 259 243 14ms 28 Apr 2025 789th tophy6 256 246 14ms 1 Apr 2025 789th LyndaS317 256 246 14ms 14 Apr 2025 791st letdank 255 247 14ms 1 Apr 2025 791st AdamGonzo1254 255 247 13ms 3 May 2025 793rd shawncrabtree 250 252 17ms 5 Jul 2025 794th punkroczombie 248 254 16ms 4 May 2025 795th Abulsamad 221 285 15ms 5 May 2025 796th aidnrox 208 303 13ms 2 May 2025 797th OffSecVik 207 304 15ms 25 Feb 2023 798th Hailee100 201 314 14ms 1 Apr 2025 799th lightediand 🇬🇧 197 319 13ms 14 Dec 2022 800th chaamsak 196 322 14ms 1 May 2025 First Prev 721–800 of 812 Next Last
