# A096971 (b-file synthesized from sequence entry) 0 1 1 1 2 4 3 13 4 49 5 181 6 685 7 2605 8 9988 9 38479 10 148879 11 577930 12 2249698 13 8777614 14 34315012 15 134377393 16 526994773 17 2069403898 18 8135377102 19 32014655626 20 126099239329 21 497083313908 22 1960943833567 23 7740893831005 24 30576064032568