# A052994 (b-file synthesized from sequence entry) 0 0 1 2 2 2 3 6 4 12 5 28 6 62 7 140 8 314 9 706 10 1586 11 3564 12 8008 13 17994 14 40432 15 90850 16 204138 17 458694 18 1030676 19 2315908 20 5203798 21 11692828 22 26273546 23 59036122 24 132652962 25 298068500 26 669753840 27 1504923218 28 3381531776 29 7598232930 30 17073074418