# A149203 (b-file synthesized from sequence entry) 0 1 1 1 2 4 3 10 4 39 5 133 6 503 7 1903 8 7473 9 29283 10 117340 11 472735 12 1923988 13 7866991 14 32415016 15 134128943 16 557609799 17 2326658582 18 9745447103 19 40938439634 20 172464891400 21 728418140034 22 3083825574858 23 13082628817159 24 55610642800671 25 236812974175072 26 1010124338572475 27 4315286500849177