# A048117 (b-file synthesized from sequence entry)
2 1
3 2
4 6
5 18
6 60
7 204
8 720
9 2580
10 9408
11 34668
12 129024
13 483672
14 1824768
15 6919752
16 26357976
17 100778472
18 386591304
19 1487221056
20 5735785176
21 22170562656
22 85866332760
23 333151068528
24 1294658562912
25 5038469947992
26 19634243736168