# A005432 (b-file synthesized from sequence entry)
0 1
1 1
2 2
3 6
4 30
5 156
6 1455
7 11300
8 151221
9 1694723
10 29594446
11 404126228
12 10594925360
13 175238308453
14 5651774693595
15 117053117995400
16 5320744503742316
17 125889331236297288
18 7598016157515302757