The Calendar hole will go live in approximately 13 days. Why not try and solve it ahead of time?
Van Eck Sequence 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 638th snoozingnewt 🇨🇦 707 52 56ms 13 Oct 2025 642nd emgordon154 707 203 502ms 6 Nov 2025 643rd KatieLG 🇬🇧 706 56 987ms 13 Oct 2021 644th Shanethegamer 🇺🇸 704 34 34ms 6 May 2021 644th MeWhenI 🇻🇦 704 34 34ms 9 Nov 2021 644th sisyphus-ppcg 🇦🇺 704 34 35ms 2 Mar 2022 647th jared-hughes 704 51 6ms 17 Jul 2022 648th snoozingnewt 🇨🇦 704 63 129ms 19 days ago 649th razetime 703 29 3ms 13 Jan 2022 650th snoozingnewt 🇨🇦 703 69 2ms 13 Oct 2025 651st Irratix 🇳🇱 702 73 41ms 7 May 2022 651st fredrik-bakke 🇳🇴 702 73 38ms 2 Oct 2022 651st fourth-bit 702 73 47ms 5 Dec 2022 651st CatsAreFluffy 702 73 23ms 17 Dec 2022 651st jmerle 🇳🇱 702 73 64ms 16 Feb 2023 651st AlexanderFair 702 73 45ms 2 Jul 2023 651st NickTheEASDude 🇺🇸 702 73 48ms 6 Aug 2024 651st AtengChen 702 73 11ms 27 Aug 2024 651st andrewjc2000 702 73 47ms 18 Jul 2025 651st madeforlosers 702 73 11ms 13 Nov 2025 661st Herbert00709 🇵🇱 702 112 58ms 1 Nov 2024 662nd GolfingSuccess 🇬🇷 701 81 18ms 11 Sep 2022 663rd MeWhenI 🇻🇦 700 194 1,704ms 7 Nov 2025 664th commandblockguy 🇺🇸 698 69 472ms 15 Jan 2024 664th TheZwierzLF 🇵🇱 698 69 414ms 26 days ago 666th luuumine 🇫🇷 698 112 116ms 16 Nov 2025 667th Shanethegamer 🇺🇸 696 73 23ms 28 Apr 2023 668th oceko 696 113 82ms 19 Feb 2024 669th MeWhenI 🇻🇦 695 114 29ms 7 Jun 2023 670th adoxography 694 53 44ms 20 Aug 2021 670th schachmattmatt 694 53 63ms 25 Sep 2021 670th anter69 🇭🇺 694 53 48ms 9 Jan 2023 670th tatzyr 🇯🇵 694 53 61ms 18 Jan 2025 674th ovs-code 🇩🇪 694 86 5ms 21 Jul 2024 675th adoxography 693 74 46ms 20 Aug 2021 675th m42km 693 74 11ms 25 Nov 2023 675th Stockoh 🇫🇷 693 74 46ms 23 Jun 2024 675th TheZwierzLF 🇵🇱 693 74 11ms 24 May 2025 679th MeWhenI 🇻🇦 692 90 41ms 17 Feb 2023 680th ian-h-chamberlain 🇺🇸 692 113 122ms 6 Jul 2022 681st frankgraziano 692 245 15ms 30 Sep 2025 682nd Shanethegamer 🇺🇸 691 78 101ms 15 Oct 2022 683rd MeWhenI 🇻🇦 690 56 2ms 4 Nov 2022 684th arjanadriaanse 🇳🇱 690 78 141ms 10 Feb 2022 684th tobeannouncd 690 78 1,395ms 8 Jan 2024 686th emgordon154 689 85 2ms 24 Dec 2021 687th Shanethegamer 🇺🇸 689 111 431ms 25 Sep 2025 687th snoozingnewt 🇨🇦 689 111 441ms 13 Oct 2025 689th JunkIce 688 70 385ms 3 Dec 2024 690th o0lit3 🇺🇸 687 45 11ms 4 May 2021 691st msbranicky 684 83 2ms 4 Aug 2023 692nd kkoenig 684 138 267ms 4 Jan 2024 693rd Naruyoko 683 60 13ms 13 Aug 2023 693rd two-bad 🇬🇧 683 60 20ms 15 Feb 2024 693rd emgordon154 683 60 21ms 6 May 2025 693rd Yax42 🇫🇷 683 60 10ms 9 Sep 2025 697th potato-jackson 683 75 15ms 10 Sep 2021 697th osmith93 683 75 20ms 14 Jun 2022 697th aksyristos 683 75 43ms 18 Jan 2023 697th celiendonze 🇨🇭 683 75 11ms 11 Apr 2023 697th programjames 683 75 42ms 3 Feb 2024 697th bob-th 683 75 28ms 26 Jul 2024 697th fkantelberg 683 75 38ms 22 Jul 2025 704th albanian-laundromat 683 248 13ms 18 Sep 2025 705th Shanethegamer 🇺🇸 680 30 3ms 5 Nov 2023 705th MeWhenI 🇻🇦 680 30 3ms 6 Nov 2023 707th albanian-laundromat 678 57 2ms 14 days ago 708th scpchicken 🇵🇼 677 48 755ms 8 Jan 2023 709th Shanethegamer 🇺🇸 677 107 341ms 27 May 2022 710th MeWhenI 🇻🇦 676 73 3ms 10 Oct 2023 711th 77Tigers 674 76 44ms 27 May 2021 711th kyleclaassen 674 76 21ms 9 Feb 2022 711th za3k 674 76 15ms 16 Oct 2022 711th cros107 🇦🇺 674 76 45ms 6 Aug 2023 715th emgordon154 674 116 144ms 22 Feb 2025 716th heypwesto 🇳🇿 672 46 2ms 3 Jun 2021 717th MeWhenI 🇻🇦 672 54 5ms 29 May 2023 718th FlorianCassayre 🇫🇷 672 61 9ms 22 Jan 2023 719th Shanethegamer 🇺🇸 672 117 78ms 28 Dec 2022 720th rucin93 🇵🇱 671 114 540ms 24 Sep 2025 First Prev 641–720 of 1,786 Next Last