# A083108 (b-file synthesized from sequence entry) 1 1 2 3 3 10 4 105 5 216 6 95095 7 9360 8 2027025 9 3203200 10 5683048371 11 76204800 12 29248404810625 13 11975040000 14 1810763157864375 15 1951364659019776 16 191898783962510625 17 690452066304000 18 241664494761081051034375