# A217017 (b-file synthesized from sequence entry) 0 1 1 1 2 2 3 9 4 216 5 4985 6 100560 7 2957857 8 136497536 9 6610096593 10 345956417280 11 23296776506201 12 1836435977198592 13 154494426214284169 14 14810872713498208256 15 1636841993390984400945 16 196590054470072062279680 17 25774473091662477588656417 18 3765032120872059152077357056