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    The Chess Move Validation hole will go live in approximately . Why not try and solve it ahead of time?

    Recent Solutions

    Hole Golfer Bytes Time Submitted
    Chess Move Validation ovs-code 52
    Gijswijt’s Sequence JOrE20 1,999
    Ellipse Perimeters ovs-code 34
    Ellipse Perimeters 2bular 31
    Floyd-Steinberg Dithering ovs-code 83
    Thue–Morse Constant HumanoidCPU 1,012
    Fibonacci Europe2048 19
    Thue–Morse Constant ovs-code 38
    Ascending Primes bstrat 24
    Tutorial quasar098 73
    Flags ovs-code 723
    Snake ovs-code 56
    Partition Numbers copy 59
    Hexagonal Spiral ovs-code 72
    Farey Sequence scpchicken 4,382
    Factorial Factorisation scpchicken 869
    Christmas Trees scpchicken 552
    Cubes scpchicken 4,129
    Lyndon Factorization 2bular 26
    SI Units ovs-code 💎 277
    Lyndon Factorization ovs-code 25
    Abundant Numbers (Long) egu555 31
    Abundant Numbers egu555 30
    Kolakoski Constant zzh1996 50
    Intersection zzh1996 31
    Mandelbrot zzh1996 69
    Tongue-twisters zzh1996 271
    ISBN zzh1996 🥇 31
    Emirp Numbers (Long) zzh1996 🥇 27
    Mahjong zzh1996 134
    Kaprekar Numbers zzh1996 47
    Topological Sort zzh1996 61
    QR Decoder zzh1996 111
    Proximity Grid zzh1996 61
    Polyominoes zzh1996 82
    Ordinal Numbers zzh1996 49
    Number Spiral zzh1996 45
    N Queens zzh1996 56
    Minesweeper zzh1996 48
    Factorial Factorisation zzh1996 52
    Cubes zzh1996 🥈 108
    Billiards zzh1996 79
    Arrows zzh1996 53
    24 Game zzh1996 🥈 108
    Niven Numbers zzh1996 🥇 21
    Emirp Numbers zzh1996 🥇 25
    Maze 2bular 48
    Yellowstone Permutation JOrE20 4,010
    Yellowstone Permutation HumanoidCPU 4,010
    Yellowstone Permutation ovs-code 54
    Billiards scpchicken 115
    Arrows scpchicken 261
    Arabic to Roman scpchicken 96
    Number Spiral JOrE20 65
    Fractions JOrE20 42
    p-adic Expansion ovs-code 91
    Ulam Sequence ovs-code 🥇 30
    SI Units zzh1996 🥈 283
    Ulam Sequence Steffan153 🥇 30
    12 Days of Christmas scpchicken 425
    Tutorial JOrE20 28
    Ulam Sequence dokutan 944
    Ulam Sequence zacjl 34
    Ascending Primes zzh1996 💎 22
    Ulam Sequence copy 35
    Alphabetic Numbers ovs-code 💎 67
    Taxicab Numbers scpchicken 36
    Fibonacci JOrE20 14
    Ascending Primes scpchicken 26
    Repeating Decimals 2bular 🥉 79
    Minesweeper blaztoma 🥈 47
    Minesweeper Steffan153 🥈 47
    Langton’s Ant ovs-code 97
    Game of Life scpchicken 42
    Ulam Sequence 2bular 🥉 33
    Inventory Sequence scpchicken 24
    Rule 110 scpchicken 53
    Number Spiral blaztoma 🥇 31
    Hilbert Curve scpchicken 204
    Musical Chords scpchicken 78
    Ulam Sequence scpchicken 🥉 33
    Snake scpchicken 95
    Connect Four ovs-code 🥇 81
    Nim zacjl 🥈 32
    Topological Sort blaztoma 53
    Connect Four 2bular 🥇 81
    Kolakoski Sequence zzh1996 🥇 15
    Sudoku zzh1996 🥈 174
    Sudoku (Fill-in) zzh1996 🥉 82
    Lucky Numbers HPWiz 30
    Snake 2bular 58
    24 Game scpchicken 114
    Polyominoes scpchicken 101
    Scrambled Sort copy 25
    Recamán copy 36
    CSS Colors ovs-code 🥇 550
    Farey Sequence codereport 🥉 31
    Maze codereport 🥇 42
    Maze ovs-code 🥇 42
    Ascending Primes codereport 🥈 23