# A191461 (b-file synthesized from sequence entry) 0 1 1 1 2 1 3 2 4 18 5 24 6 480 7 720 8 23520 9 100800 10 1874880 11 3628800 12 341953920 13 479001600 14 36739422720 15 468583315200 16 8960682931200 17 20922789888000 18 4289844445286400 19 6402373705728000 20 1012647189038284800 21 18895538930171904000 22 350378437544239104000