# A264235 (b-file synthesized from sequence entry) 0 1 1 2 2 3 3 8 4 15 5 144 6 35 7 5760 8 2835 9 44800 10 6237 11 43545600 12 25025 13 6706022400 14 13030875 15 229605376 16 10854718875 17 376610217984000 18 282907625 19 128047474114560000 20 311834363841 21 166487326720000 22 407510816383125 23 26976017466662584320000 24 62628675484375