The Calendar hole will go live in approximately 11 days. Why not try and solve it ahead of time?
Catalan Numbers 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 320th nwellnhof 🇩🇪 921 33 240ms 1 Feb 2022 320th bitsandbeyond 🇳🇱 921 33 261ms 6 Oct 2025 323rd sean-niemann 🇺🇸 921 38 673ms 21 Sep 2025 323rd fuzzylojik-golf 🇺🇸 921 38 687ms 21 Sep 2025 325th Steffan153 🇫🇮 918 47 121ms 3 Aug 2024 325th DialFrost 🇸🇬 918 47 118ms 3 Aug 2024 325th rucin93 🇵🇱 918 47 129ms 3 Aug 2024 325th sean-niemann 🇺🇸 918 47 127ms 3 Aug 2024 325th JayXon 🇺🇸 918 47 122ms 6 Aug 2024 325th Lydxn 🇨🇦 918 47 120ms 6 Aug 2024 325th emplv 🇱🇻 918 47 117ms 29 Oct 2024 325th lukegustafson 🇺🇸 918 47 118ms 3 Apr 2025 333rd zacjl 917 44 1,564ms 3 Dec 2024 333rd 2bular 917 44 24ms 18 Jun 2025 335th nwellnhof 🇩🇪 917 79 391ms 30 Jan 2022 335th JayXon 🇺🇸 917 79 387ms 30 Jan 2022 335th Lydxn 🇨🇦 917 79 401ms 31 Jan 2022 335th btnlq 917 79 386ms 11 Mar 2023 335th Yax42 🇫🇷 917 79 364ms 1 Aug 2025 335th AdrienHache 🇫🇷 917 79 362ms 14 Aug 2025 335th fuzzylojik-golf 🇺🇸 917 79 375ms 8 Sep 2025 335th sean-niemann 🇺🇸 917 79 375ms 21 Sep 2025 343rd Lydxn 🇨🇦 916 54 911ms 29 Jan 2022 343rd JayXon 🇺🇸 916 54 951ms 29 Jan 2022 343rd primo-ppcg 🇹🇭 916 54 976ms 29 Jan 2022 343rd sisyphus-ppcg 🇦🇺 916 54 1,047ms 2 Feb 2022 343rd MeWhenI 🇻🇦 916 54 993ms 13 Nov 2022 343rd stefangimmillaro 916 54 949ms 9 Dec 2022 343rd Steffan153 🇫🇮 916 54 995ms 11 Feb 2023 343rd emgordon154 916 54 857ms 17 Nov 2024 343rd DialFrost 🇸🇬 916 54 937ms 17 Nov 2024 343rd sean-niemann 🇺🇸 916 54 1,003ms 30 Dec 2024 343rd edsrzf 🇳🇿 916 54 968ms 15 Jan 2025 343rd pardouin 🇫🇷 916 54 990ms 10 Apr 2025 343rd fuzzylojik-golf 🇺🇸 916 54 903ms 8 Sep 2025 356th Lydxn 🇨🇦 913 49 25ms 29 Jan 2022 356th btnlq 913 49 25ms 29 Jan 2022 358th itsh01 912 43 9ms 10 Feb 2022 358th 051 🇸🇬 912 43 8ms 19 Aug 2022 358th tayloia 🇬🇧 912 43 9ms 12 Jan 2023 358th eranws 912 43 9ms 8 Feb 2024 358th voytxt 🇨🇿 912 43 8ms 5 May 2024 358th Yewzir 🇧🇪 912 43 8ms 7 May 2024 358th dmrichwa 🇺🇸 912 43 9ms 22 Sep 2024 358th a6166231 🇨🇳 912 43 9ms 25 Apr 2025 358th dokutan 912 43 9ms 22 Sep 2025 367th RYNO8 912 47 11ms 18 Feb 2022 367th TFeld00 🇩🇰 912 47 9ms 22 Apr 2022 367th LukasFolwarczny 🇨🇿 912 47 11ms 16 Sep 2022 367th commandblockguy 🇺🇸 912 47 9ms 18 Sep 2022 367th KatieLG 🇬🇧 912 47 11ms 6 Oct 2022 367th betaveros 912 47 11ms 30 Dec 2022 367th Just4FunCoder 912 47 11ms 23 Mar 2023 367th vishwathg 912 47 11ms 4 Apr 2023 367th Schreipfelerer 912 47 11ms 9 Apr 2023 367th quimey 912 47 10ms 23 Jun 2023 367th dranjohn 912 47 9ms 16 Sep 2023 367th keelimeguy 🇺🇸 912 47 11ms 16 Dec 2023 367th bob-th 912 47 11ms 22 Jan 2024 367th fgrosshans 🇫🇷 912 47 11ms 16 Jul 2024 367th moustave 912 47 10ms 4 Dec 2024 367th Bulmenisaurus 912 47 13ms 6 Feb 2025 367th xiaoyiming123 912 47 9ms 23 Jul 2025 367th InigoK 🇺🇸 912 47 9ms 9 Aug 2025 367th luuumine 🇫🇷 912 47 13ms 21 Nov 2025 367th Lv0Sys 🇵🇱 912 47 9ms 13 days ago 387th fuzzylojik-golf 🇺🇸 912 119 419ms 24 Sep 2025 387th sean-niemann 🇺🇸 912 119 454ms 24 Sep 2025 387th JayXon 🇺🇸 912 119 394ms 25 Sep 2025 387th nwellnhof 🇩🇪 912 119 397ms 25 Sep 2025 391st clockworknazo 911 56 5ms 30 Sep 2022 391st Lydxn 🇨🇦 911 56 5ms 28 Feb 2023 393rd Lydxn 🇨🇦 911 58 5ms 29 Jan 2022 393rd primo-ppcg 🇹🇭 911 58 6ms 29 Jan 2022 393rd AlephSquirrel 911 58 5ms 16 Jan 2023 393rd ovs-code 🇩🇪 911 58 5ms 11 Mar 2023 393rd varhammer 🇷🇺 911 58 5ms 19 Oct 2024 393rd kg583 🇺🇸 911 58 5ms 21 Oct 2024 393rd CLOStrophobic 🇮🇹 911 58 6ms 17 Jan 2025 393rd zacjl 911 58 5ms 21 Jan 2025 First Prev 321–400 of 1,982 Next Last