# A149878 (b-file synthesized from sequence entry) 0 1 1 2 2 5 3 14 4 42 5 140 6 480 7 1710 8 6227 9 23087 10 87495 11 335253 12 1304117 13 5120189 14 20286069 15 81087950 16 326175588 17 1321918434 18 5385669252 19 22062590893 20 90821095614 21 375419697147 22 1558667802107 23 6493810637583 24 27152832780694 25 113894033778109 26 479137002109941 27 2021504946377131 28 8550206541089202