# A143647 (b-file synthesized from sequence entry)
0 1
1 5
2 28
3 170
4 1084
5 7100
6 47152
7 315320
8 2115856
9 14221520
10 95666368
11 643790240
12 4333242304
13 29169037760
14 196359046912
15 1321871638400
16 8898817351936
17 59906997474560
18 403295993003008
19 2715005985589760
20 18277548009831424