# A049146 (b-file synthesized from sequence entry) 1 1 2 1 3 2 4 4 5 10 6 24 7 66 8 173 9 498 10 1378 11 4070 12 11680 13 35078 14 103292 15 313980 16 942133 17 2890878 18 8798182 19 27204516 20 83704806 21 260493354 22 808445448 23 2529836520 24 7906101138 25 24858833998 26 78131339008 27 246694899708 28 779057755912