# A025274 (b-file synthesized from sequence entry) 1 1 2 1 3 1 4 0 5 2 6 5 7 14 8 42 9 122 10 360 11 1068 12 3181 13 9526 14 28654 15 86558 16 262528 17 799212 18 2441538 19 7483052 20 23004500 21 70921492 22 219226064 23 679328952 24 2109948221 25 6567539814 26 20483936790 27 64010196918 28 200382350016 29 628344541644 30 1973428795542