# A113860 (b-file synthesized from sequence entry) 0 1 1 3 2 7 3 23 4 87 5 599 6 1623 7 3671 8 7767 9 15959 10 81495 11 343639 12 867927 13 1916503 14 18693719 15 152911447 16 421346903 17 958217815 18 2031959639 19 4179443287 20 12769377879 21 1112281005655 22 9908374027863 23 27500560072279 24 97869304249943