The first, 40, terms of the sequence enumerating permutations of length n suc\
    h that pi[i+6]-pi[i] is never 6 are



[1, 2, 6, 24, 120, 720, 4920, 37488, 319644, 3033264, 31784280, 364902480,

    4538652840, 61102571376, 885045657564, 13722397569072, 226742901078120,

    3977354871110160, 73816786920489720, 1444940702597713008,

    29750236302549282948, 642693417769786746864, 14535097378893765189240,

    343437047642562028552080, 8462159221483607741355240,

    217058738026004962847383728, 5786962567831579779470339100,

    160128502445222440732972796400, 4592452781535034288371178753320,

    136343280150947006461513508855760, 4185311581132447162603024228097880,

    132694329443246698408448358899760816, 4340734289338815557327414134657155924,

    146367115445626267993586873411844272688,

    5082781953788490662193307110992472897240,

    181621838046071385634617423863860872183120,

    6672600066703796190024884102084852552358120,

    251856702941793193891091324971698132180278640,

    9759596377265933158678288301015279255233123068,

    388002811128164279929178134769493739939953127728]



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