# A024736 (b-file synthesized from sequence entry) 1 1 2 2 3 4 4 9 5 20 6 44 7 97 8 230 9 540 10 1257 11 2920 12 7128 13 17225 14 41276 15 98848 16 244857 17 602368 18 1472564 19 3594009 20 9001188 21 22402820 22 55447385 23 137104808 24 345794100 25 868000657 26 2169191678 27 5413976096 28 13735048385 29 34694002916 30 87290093640 31 219428919825