# A035481 (b-file synthesized from sequence entry) 0 1 1 1 2 1 3 1 4 4 5 6 6 456 7 6240 8 10936320 9 1225566720 10 130025295912960 11 252282619805368320 12 2209617218725251404267520 13 98758655816833727741338583040