# A365990 (b-file synthesized from sequence entry) 0 1 1 0 2 0 3 0 4 6 5 0 6 0 7 0 8 2520 9 40320 10 0 11 0 12 7484400 13 345945600 14 6227020800 15 0 16 81729648000 17 7410154752000 18 307697854464000 19 6402373705728000 20 2375880867360000 21 354798209525760000 22 25460995321681920000 23 1090665702016450560000 24 26003493399464380800000