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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
    Thue–Morse Constant edsrzf 71
    Thue–Morse Constant HumanoidCPU 1,012
    Thue–Morse Constant kg583 76
    12 Days of Christmas edsrzf 🥇 326
    CSS Colors kg583 🥈 726
    Continued Fractions kg583 🥈 149
    Transpose Sentence edsrzf 💎 148
    Transpose Sentence kg583 🥈 160
    Intersection kg583 🥈 166
    Tutorial quasar098 207
    Quine LostSyntax21 54
    Emojify scpchicken 705
    DFA Simulator scpchicken 1,981
    Day of Week scpchicken 1,551
    CSS Colors scpchicken 4,264
    Continued Fractions scpchicken 🥉 1,749
    Connect Four scpchicken 🥈 1,464
    Catalan Numbers edsrzf 🥇 56
    12 Days of Christmas kg583 🥇 326
    Calendar edsrzf 🥇 227
    Calendar kg583 🥇 227
    Card Number Validation scpchicken 811
    Calendar scpchicken 🥉 1,662
    Billiards scpchicken 1,483
    Arrows scpchicken 1,078
    Foo Fizz Buzz Bar scpchicken 6,729
    Farey Sequence scpchicken 5,139
    Fibonacci scpchicken 175
    Factorial Factorisation scpchicken 873
    Emirp Numbers (Long) scpchicken 1,406
    Emirp Numbers scpchicken 182
    Divisors scpchicken 1,276
    Diamonds scpchicken 1,202
    Collatz scpchicken 4,236
    Christmas Trees scpchicken 610
    Cubes scpchicken 4,222
    Alphabetic Numbers scpchicken 4,906
    Gijswijt’s Sequence scpchicken 3,010
    Catalan’s Constant scpchicken 1,014
    Catalan Numbers scpchicken 2,982
    ASCII Table scpchicken 302
    Ascending Primes scpchicken 622
    Arithmetic Numbers scpchicken 45,340
    Abundant Numbers (Long) scpchicken 1,220
    Abundant Numbers scpchicken 219
    99 Bottles of Beer scpchicken 12,194
    24 Game scpchicken 13,804
    12 Days of Christmas scpchicken 792
    Hexagonal Spiral bitsandbeyond 447
    Pernicious Numbers bitsandbeyond 87
    Christmas Trees edsrzf 🥇 68
    Diamonds edsrzf 💎 97
    Ordinal Numbers kg583 🥈 113
    Tongue-twisters kg583 374
    Forsyth–Edwards Notation edsrzf 🥈 194
    99 Bottles of Beer Xzyaihni 367
    12 Days of Christmas zzh1996 344
    N Queens edsrzf 💎 132
    Yellowstone Permutation HumanoidCPU 4,020
    Arabic to Roman scpchicken 🥇 57
    φ dokutan 79
    Gijswijt’s Sequence edsrzf 💎 122
    N Queens MostParsingVex 🥉 277
    Foo Fizz Buzz Bar Steffan153 🥇 109
    Foo Fizz Buzz Bar kg583 🥇 109
    Foo Fizz Buzz Bar edsrzf 🥇 109
    Fizz Buzz edsrzf 🥇 78
    brainfuck scpchicken 2,384
    Roman to Arabic Steffan153 🥇 87
    Ulam Sequence dokutan 🥈 572
    Sierpiński Triangle edsrzf 🥈 81
    Pernicious Numbers edsrzf 🥉 57
    Jacobi Symbol edsrzf 💎 183
    Intersection edsrzf 💎 154
    Arrows AlephSquirrel 241
    ISBN edsrzf 🥈 146
    Kolakoski Constant kg583 🥈 114
    Kolakoski Sequence kg583 🥈 80
    ISBN kg583 💎 145
    Ulam Sequence edsrzf 💎 107
    Lucky Tickets edsrzf 💎 149
    Smooth Numbers kg583 122
    Recamán edsrzf 🥇 84
    Chess960 Decoder LostSyntax21 322
    United States deglebe 995
    brainfuck edsrzf 💎 253
    United States GolfingSuccess 1,355
    Evil Numbers Europe2048 103
    United States madex 🥈 212
    United States blaztoma 296
    United States AlephSquirrel 🥉 279
    Pernicious Numbers (Long) kg583 🥇 65
    Jacobi Symbol kg583 🥈 187
    λ vhoulbreque 1,020
    Alphabetic Numbers retrohun 3,904
    Time Distance kg583 💎 272
    Polyominoes kg583 💎 246
    Pernicious Numbers albanian-laundromat 109
    Pernicious Numbers btjones0 130
    Rule 110 edsrzf 💎 114