# A055585 (b-file synthesized from sequence entry) 0 1 1 6 2 25 3 88 4 280 5 832 6 2352 7 6400 8 16896 9 43520 10 109824 11 272384 12 665600 13 1605632 14 3829760 15 9043968 16 21168128 17 49152000 18 113311744 19 259522560 20 590872576 21 1337982976 22 3014656000 23 6761218048 24 15099494400 25 33587986432 26 74440507392