# A020127 (b-file synthesized from sequence entry)
0 1
1 1
2 2
3 5
4 16
5 74
6 427
7 2901
8 22625
9 199095
10 1951128
11 21072176
12 248651669
13 3182741352
14 43921830648
15 650043093589
16 10270680878694
17 172547438762056
18 3071344409964595
19 57741274907334371
20 1143277243165220534