The Gray Code Decoder and Gray Code Encoder holes will go live in approximately 8 days. Why not try and solve them ahead of time?
Van Eck 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 641st NewDefectus 🇮🇱 721 57 49ms 6 Dec 2021 642nd edsrzf 🇳🇿 721 70 10ms 14 Dec 2024 643rd eranws 719 57 10ms 9 Sep 2022 643rd iczelia 🇩🇪 719 57 12ms 11 Oct 2025 645th KatieLG 🇬🇧 719 67 429ms 1 Oct 2025 645th albanian-laundromat 719 67 407ms 23 Oct 2025 647th stefangimmillaro 719 75 117ms 25 Jun 2023 648th inventshah 719 131 93ms 9 Sep 2022 649th cure-honey 🇯🇵 717 109 128ms 11 Jul 2021 649th mousetail 🇳🇱 717 109 121ms 18 Jan 2024 651st emgordon154 715 101 485ms 8 Feb 2026 652nd scpchicken 🇵🇼 713 48 555ms 8 Jan 2023 653rd emplv 🇱🇻 713 118 26ms 29 Jun 2022 654th kyleclaassen 712 76 22ms 9 Feb 2022 654th za3k 712 76 17ms 16 Oct 2022 654th cros107 🇦🇺 712 76 45ms 6 Aug 2023 654th elgan65536 🇺🇸 712 76 46ms 7 Apr 2024 654th wh3n3v3r 🇨🇿 712 76 18ms 14 Nov 2024 659th sean-niemann 🇺🇸 710 110 130ms 9 Jun 2025 660th rak1507 🇬🇧 709 76 137ms 29 Jun 2021 660th GrayJoKing 🇦🇺 709 76 130ms 14 Mar 2022 662nd emgordon154 708 52 41ms 27 Nov 2024 662nd olleicua 🇺🇸 708 52 46ms 25 Feb 2025 662nd codereport 🇨🇦 708 52 33ms 21 Apr 2025 662nd snoozingnewt 🇨🇦 708 52 38ms 13 Oct 2025 666th Irratix 🇳🇱 708 111 63ms 3 Jan 2022 666th Yewzir 🇧🇪 708 111 59ms 11 Feb 2024 668th KatieLG 🇬🇧 707 56 1,480ms 13 Oct 2021 669th emgordon154 707 203 1,463ms 6 Nov 2025 670th jared-hughes 705 51 6ms 17 Jul 2022 671st razetime 704 29 3ms 13 Jan 2022 672nd Shanethegamer 🇺🇸 704 34 34ms 6 May 2021 672nd MeWhenI 🇻🇦 704 34 34ms 9 Nov 2021 672nd sisyphus-ppcg 🇦🇺 704 34 34ms 2 Mar 2022 672nd DialFrost 🇸🇬 704 34 34ms 18 Jan 2023 676th snoozingnewt 🇨🇦 703 69 2ms 13 Oct 2025 677th LeeCamp 703 77 25ms 23 Dec 2021 677th Just4FunCoder 703 77 20ms 23 Mar 2023 677th codewrite 🇬🇧 703 77 11ms 9 Jul 2025 677th vhoulbreque 🇫🇷 703 77 11ms 3 Dec 2025 681st MeWhenI 🇻🇦 703 194 1,704ms 7 Nov 2025 682nd albanian-laundromat 702 55 2ms 11 days ago 683rd Herbert00709 🇵🇱 702 112 56ms 1 Nov 2024 684th GolfingSuccess 🇬🇷 701 81 18ms 11 Sep 2022 685th albanian-laundromat 701 120 26ms 11 days ago 686th emgordon154 700 85 2ms 24 Dec 2021 687th commandz0 🇺🇸 698 69 493ms 15 Jan 2024 687th TheZwierzLF 🇵🇱 698 69 469ms 22 Nov 2025 689th luuumine 🇫🇷 698 112 123ms 16 Nov 2025 690th Shanethegamer 🇺🇸 697 111 457ms 25 Sep 2025 690th snoozingnewt 🇨🇦 697 111 431ms 13 Oct 2025 692nd MeWhenI 🇻🇦 697 114 27ms 7 Jun 2023 693rd Shanethegamer 🇺🇸 696 73 27ms 28 Apr 2023 694th oceko 696 113 63ms 19 Feb 2024 695th frankgraziano 695 245 15ms 30 Sep 2025 696th adoxography 694 53 41ms 20 Aug 2021 696th schachmattmatt 694 53 38ms 25 Sep 2021 696th tatzyr 🇯🇵 694 53 44ms 18 Jan 2025 699th Indivicivet 694 78 58ms 26 Oct 2021 699th SirFireball3521 694 78 17ms 14 Mar 2023 699th Alex-x90 🇺🇸 694 78 19ms 6 Nov 2023 702nd MeWhenI 🇻🇦 694 90 41ms 17 Feb 2023 703rd DialFrost 🇸🇬 692 52 10ms 29 Dec 2025 704th ian-h-chamberlain 🇺🇸 692 113 128ms 6 Jul 2022 705th Shanethegamer 🇺🇸 691 73 50ms 8 Apr 2024 706th arjanadriaanse 🇳🇱 691 78 141ms 10 Feb 2022 706th Shanethegamer 🇺🇸 691 78 116ms 15 Oct 2022 706th tobeannouncd 691 78 1,395ms 8 Jan 2024 709th MeWhenI 🇻🇦 690 56 2ms 4 Nov 2022 710th kkoenig 690 138 292ms 4 Jan 2024 711th o0lit3 🇺🇸 688 45 12ms 4 May 2021 712th HumanoidCPU 688 70 480ms 25 May 2024 713th albanian-laundromat 687 248 13ms 18 Sep 2025 714th Fishron 685 79 51ms 19 Oct 2021 714th pascscha 685 79 18ms 28 Mar 2022 714th 2011-Chan-Ethan 685 79 62ms 10 Jul 2023 714th zgialor-lab 685 79 16ms 13 days ago 718th msbranicky 684 83 2ms 4 Aug 2023 719th voytxt 🇨🇿 683 55 141ms 3 Aug 2024 720th Naruyoko 683 60 14ms 13 Aug 2023 First Prev 641–720 of 1,875 Next Last