# A049154 (b-file synthesized from sequence entry)
0 1
1 1
2 3
3 9
4 31
5 113
6 431
7 1699
8 6869
9 28337
10 118827
11 505077
12 2171403
13 9426025
14 41260639
15 181923359
16 807230625
17 3601980785
18 16152883683
19 72760511753
20 329066924255
21 1493649861729
22 6802136334927
23 31070513911731