# A362798 (b-file synthesized from sequence entry) 0 1 1 1 2 2 3 6 4 48 5 360 6 2820 7 31500 8 393568 9 5111568 10 78491520 11 1345893120 12 24286008384 13 483716087712 14 10526811186528 15 241867328844960 16 5957816820215040 17 157412355684364800 18 4380674530640290560 19 128826276098289179904 20 4010282529115722232320