# A046238 (b-file synthesized from sequence entry) 1 0 2 1 3 8 4 64 5 512 6 4096 7 125000 8 1000000 9 8000000 10 40707584 11 325660672 12 2605285376 13 13858588808 14 110868710464 15 886949683712 16 4748408986112 17 37987271888896 18 303898175111168 19 1628455122125000 20 13027640977000000