# A005642 (b-file synthesized from sequence entry) 2 1 3 3 4 7 5 24 6 117 7 663 8 4824 9 40367 10 381554 11 4001849 12 46043780 13 576018785 14 7783281188 15 112953364381 16 1752128923245 17 28930230194371 18 506596534953769