# A305108 (b-file synthesized from sequence entry) 0 1 1 1 2 12 3 342 4 16080 5 1090400 6 99884736 7 11885278104 8 1786708056832 9 331931252093472 10 74805826012157600 11 20127855750577630968 12 6377560491906482613120 13 2351353212746078192866032 14 998307775668524681354287776 15 483648245019895895020555792200 16 265226237170176555086800587134976 17 163463812810277012465203148994919744 18 112505648337664454361768261713783693856