# A012341 (b-file synthesized from sequence entry) 0 0 1 2 2 8 3 248 4 11328 5 1091232 6 148080000 7 30317577600 8 8228536780800 9 2957031184028160 10 1336782441018009600 11 749500660718368634880 12 508063303148296391147520 13 410659058984740631962951680