# A109268 (b-file synthesized from sequence entry) 0 1 1 1 2 4 3 11 4 36 5 119 6 407 7 1418 8 5018 9 17971 10 64989 11 236915 12 869518 13 3209735 14 11907644 15 44368636 16 165957615 17 622880402 18 2345005449 19 8852862717 20 33505203060 21 127096279124 22 483127286394 23 1840030664115 24 7020349647422