The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 7 days. Why not try and solve them ahead of time?
Inventory Sequence 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 Calendar Card Number Validation Catalan Numbers Catalan’s Constant Christmas Trees Collatz Continued Fractions 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 Multitap Input 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 Alphabetic Numbers Apéry’s Constant Binary Lambda Calculus Connect Four Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Rectangle Fill Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial All Languages ><> ALGOL 68 ArkScript 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 APL Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight Lily Luau Odin Picat Qore Racket Rebol Rexx Scala Squirrel Stax Uiua Umka Vala Vyxal Bytes Chars Scoring Bytes Chars Language All ><> ALGOL 68 ArkScript 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 APL Arturo Befunge BQN CJam CoffeeScript Egel Fennel Harbour Hare Haxe Hush Hy iogii Knight Lily 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 Calendar Card Number Validation Catalan Numbers Catalan’s Constant Christmas Trees Collatz Continued Fractions 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 Multitap Input 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 Alphabetic Numbers Apéry’s Constant Binary Lambda Calculus Connect Four Crossword CSS Colors (Inverse) CSS Grid Ellipse Perimeters Flags Floyd-Steinberg Dithering Gray Code Decoder Gray Code Encoder Hexagonal Spiral Highly Composite Numbers NFA Simulator Numbrix Odd Polyomino Tiling p-adic Expansion Polygon Triangulations QR Encoder Quadratic Formula Rectangle Fill Semiprime Numbers Smooth Numbers Snake Sphenic Numbers Taxicab Numbers Turtle Tutorial # Golfer Points Bytes Time Submitted 640th tayloia 🇬🇧 772 64 10ms 9 Jan 2023 640th Argeento 🇵🇱 772 64 10ms 29 Aug 2023 643rd MeWhenI 🇻🇦 772 84 124ms 24 Nov 2022 644th jerrandolph 772 123 270ms 21 Dec 2023 645th janbehrens 🇩🇪 769 42 3ms 20 Nov 2022 645th SirBogman 🇺🇸 769 42 3ms 22 Nov 2022 647th Shanethegamer 🇺🇸 769 47 40ms 31 Jan 2023 647th olleicua 🇺🇸 769 47 40ms 5 Jan 2024 649th MichalMarsalek 🇨🇿 767 68 23ms 20 Nov 2022 649th NerdyMcNerd42 767 68 15ms 22 Jan 2023 649th SB-945 767 68 15ms 19 Feb 2024 649th nemoyatpeace 767 68 15ms 15 Jan 2026 653rd MeWhenI 🇻🇦 766 81 2ms 22 Jul 2024 654th GolfingSuccess 🇬🇷 762 63 9ms 19 Dec 2024 655th Stockoh 🇫🇷 762 65 455ms 24 Jun 2024 655th TheZwierzLF 🇵🇱 762 65 441ms 11 Dec 2025 657th strout 762 85 140ms 14 Dec 2023 658th edsrzf 🇳🇿 759 124 28ms 10 hours ago 659th MeWhenI 🇻🇦 758 53 1ms 10 Feb 2023 660th andre-lameirinhas 🇵🇹 756 69 15ms 23 Feb 2023 660th jtaxen 756 69 15ms 30 Mar 2024 660th FranklinJiaChen 756 69 39ms 5 Aug 2024 660th dokutan 756 69 40ms 15 Aug 2024 660th webmiche 756 69 11ms 28 Nov 2025 665th albanian-laundromat 755 115 25ms 12 days ago 666th Babafaba 754 78 2ms 14 Oct 2025 667th KatieLG 🇬🇧 753 48 39ms 1 Sep 2024 668th yeminghan2021 750 102 60ms 1 Feb 2025 669th bac0id 749 66 11ms 30 Jun 2024 669th CaedenHarper 🇨🇦 749 66 10ms 23 Aug 2025 669th snoozingnewt 🇨🇦 749 66 13ms 13 Oct 2025 669th iczelia 🇩🇪 749 66 10ms 23 Oct 2025 673rd jared-hughes 748 50 9ms 22 Nov 2022 674th msbranicky 747 74 3ms 10 Oct 2023 675th pardouin 🇫🇷 746 57 147ms 26 Jul 2025 676th b10011 🇫🇮 745 70 16ms 9 Jan 2023 676th knutae 🇳🇴 745 70 15ms 29 Dec 2023 676th wobblybits 745 70 17ms 18 Aug 2025 676th jacekwladzinski 745 70 29ms 4 Oct 2025 680th blaztoma 🇱🇹 744 54 2ms 2 Sep 2025 680th albanian-laundromat 744 54 2ms 21 Dec 2025 682nd MichalMarsalek 🇨🇿 742 89 410ms 20 Nov 2022 683rd snoozingnewt 🇨🇦 739 84 2ms 13 Oct 2025 684th anter69 🇭🇺 738 49 38ms 9 Feb 2023 685th tri1212 🇻🇳 735 71 42ms 30 Jun 2024 685th PyryL 🇫🇮 735 71 16ms 23 Aug 2024 685th YAJUE114514 735 71 15ms 13 Jul 2025 685th madeforlosers 735 71 15ms 13 Nov 2025 689th blaztoma 🇱🇹 735 90 2,698ms 2 Sep 2025 690th klixel 🇨🇦 735 104 413ms 17 Oct 2024 691st MeWhenI 🇻🇦 735 197 13ms 1 Aug 2023 692nd JRaspass 🇬🇧 734 44 3ms 20 Nov 2022 693rd frankgraziano 733 51 136ms 27 Feb 2025 694th ovs-code 🇩🇪 733 58 157ms 3 Aug 2024 695th kg583 🇺🇸 731 85 18ms 5 Dec 2025 696th Shanethegamer 🇺🇸 730 55 5ms 22 Nov 2022 696th snoozingnewt 🇨🇦 730 55 2ms 13 Oct 2025 698th msbranicky 730 103 367ms 10 Jan 2024 699th MeWhenI 🇻🇦 730 129 29ms 5 Jun 2023 700th blaztoma 🇱🇹 728 89 108ms 17 Aug 2025 701st emgordon154 727 91 2,683ms 28 Oct 2024 702nd SirBogman 🇺🇸 726 43 190ms 20 Nov 2022 703rd Irratix 🇳🇱 726 81 2ms 11 Dec 2022 704th ovs-code 🇩🇪 726 95 30ms 2 Jul 2024 705th msbranicky 725 72 15ms 19 Aug 2023 705th adamnielson42 🇺🇸 725 72 15ms 21 Aug 2023 705th Masttest 725 72 16ms 15 Feb 2024 705th Code-Coder-coder 725 72 14ms 24 Nov 2025 709th TFeld00 🇩🇰 723 50 40ms 3 Sep 2024 710th KatieLG 🇬🇧 723 53 1,465ms 3 Jan 2024 711th Shanethegamer 🇺🇸 722 86 8ms 23 Nov 2022 711th blaztoma 🇱🇹 722 86 2ms 2 Sep 2025 713th MeWhenI 🇻🇦 721 92 1,025ms 21 May 2023 714th annaproxy 721 106 59ms 23 Jan 2023 714th Babafaba 721 106 2,464ms 14 Oct 2025 716th angel-p57 🇯🇵 721 236 5ms 7 Dec 2023 717th Shanethegamer 🇺🇸 720 57 245ms 19 Nov 2022 718th Chinay-Domitrix 🇺🇸 719 92 2,532ms 5 days ago 719th DialFrost 🇸🇬 718 69 344ms 31 Jul 2024 719th dokutan 718 69 413ms 15 Aug 2024 First Prev 641–720 of 1,679 Next Last