# A052598 (b-file synthesized from sequence entry) 0 1 1 0 2 4 3 12 4 144 5 1200 6 15840 7 211680 8 3467520 9 61689600 10 1241049600 11 27223257600 12 654316185600 13 16999766784000 14 476167826534400 15 14282419447296000 16 457079267893248000 17 15539983733514240000