# A009668 (b-file synthesized from sequence entry) 0 1 1 4 2 32 3 432 4 10752 5 504832 6 35418112 7 3115462656 8 333569720320 9 44698511474688 10 7574890049699840 11 1575934549490139136 12 387157222106970718208 13 110017544405171642040320