# A005323 (b-file synthesized from sequence entry) 3 1 4 4 5 14 6 44 7 133 8 392 9 1140 10 3288 11 9438 12 27016 13 77220 14 220584 15 630084 16 1800384 17 5147328 18 14727168 19 42171849 20 120870324 21 346757334 22 995742748 23 2862099185 24 8234447672 25 23713180780 26 68350541480 27 197188167735 28 569371325796