# A319221 (b-file synthesized from sequence entry) 0 1 1 2 2 0 3 24 4 144 5 960 6 4608 7 74048 8 859952 9 9568800 10 109975680 11 1647979872 12 23917274304 13 358378620704 14 5528847787008 15 94307761212304 16 1632598198916544 17 29205907283227776 18 538335591996965760 19 10388234139989630128 20 205386383159397554688 21 4173254005731822569088