# A088984 (b-file synthesized from sequence entry) 2 2 3 3 4 40 5 105 6 1584 7 5985 8 107136 9 530145 10 11116800 11 68139225 12 1644364800 13 12034447425 14 329001523200 15 2801155982625 16 85619242598400 17 831764543234625 18 28117244819865600 19 307025061241523625 20 11374945402060800000