# A024958 (b-file synthesized from sequence entry) 1 3 2 1 3 1 4 3 5 9 6 28 7 87 8 270 9 838 10 2682 11 8568 12 27325 13 87087 14 284940 15 929773 16 3026424 17 9843471 18 32691629 19 108290562 20 357839667 21 1181136576 22 3967571310 23 13290977466 24 44410377199 25 148240940865 26 501864577470 27 1694984858142 28 5711630686332