# A054442 (b-file synthesized from sequence entry) 0 1 1 3 2 9 3 22 4 54 5 123 6 281 7 618 8 1362 9 2934 10 6330 11 13452 12 28620 13 60243 14 126921 15 265282 16 554874 17 1153506 18 2399390 19 4966740 20 10286196 21 21219038 22 43790154 23 90076452 24 185353204 25 380364108 26 780786516 27 1599015192 28 3275589144