# A006772 (b-file synthesized from sequence entry) 1 0 2 1 3 3 4 14 5 70 6 370 7 2028 8 11452 9 66172 10 389416 11 2326202 12 14070268 13 86010680 14 530576780 15 3298906810 16 20653559846 17 130099026600 18 823979294284 19 5244162058026 20 33523117491920 21 215150177410088 22 1385839069134800 23 8956173544332434 24 58056703069399056 25 377396656568011618 26 2459614847765495754 27 16068572108927106202