# A171074 (b-file synthesized from sequence entry) 1 1 2 4 3 18 4 68 5 250 6 922 7 3430 8 12868 9 48618 10 184754 11 705430 12 2704154 13 10400598 14 40116598 15 155117518 16 601080388 17 2333606218 18 9075135298 19 35345263798 20 137846528818 21 538257874438 22 2104098963718 23 8233430727598 24 32247603683098