# A181290 (b-file synthesized from sequence entry)
0 0
1 2
2 11
3 52
4 227
5 944
6 3800
7 14944
8 57748
9 220128
10 829968
11 3101376
12 11502704
13 42393088
14 155392768
15 566918144
16 2059768384
17 7456496128
18 26905720576
19 96804463616
20 347386161920
21 1243665567744
22 4442849839104
23 15840448094208