# A097164 (b-file synthesized from sequence entry) 0 1 1 4 2 8 3 20 4 36 5 84 6 148 7 340 8 596 9 1364 10 2388 11 5460 12 9556 13 21844 14 38228 15 87380 16 152916 17 349524 18 611668 19 1398100 20 2446676 21 5592404 22 9786708 23 22369620 24 39146836 25 89478484 26 156587348 27 357913940 28 626349396 29 1431655764 30 2505397588