# A124541 (b-file synthesized from sequence entry)
0 1
1 1
2 4
3 15
4 63
5 295
6 1502
7 8167
8 46873
9 281672
10 1761798
11 11418480
12 76415644
13 526594846
14 3728435747
15 27073765165
16 201325681384
17 1531247489953
18 11899881220174
19 94409837555587
20 764105555574024
21 6304959856949278