# A047923 (b-file synthesized from sequence entry) 0 1 1 6 2 29 3 97 4 343 5 1131 6 3338 7 10336 8 29644 9 88555 10 260497 11 728358 12 2103284 13 6020698 14 16594432 15 46969365 16 128670281 17 361020986 18 1008411198 19 2742388946 20 7613161908 21 20632925370 22 56988914979 23 156977658446 24 423559114311