# A012754 (b-file synthesized from sequence entry) 0 1 1 2 2 12 3 280 4 13328 5 1016608 6 120249536 7 19735743872 8 4349101334784 9 1233253332705792 10 437938810884459520 11 190333673674118699008 12 99369086035110941036544 13 61369835997419856216006656