# A181294 (b-file synthesized from sequence entry)
0 0
1 2
2 10
3 46
4 198
5 816
6 3264
7 12776
8 49192
9 186976
10 703328
11 2623072
12 9712864
13 35746816
14 130873088
15 476961920
16 1731331200
17 6262393344
18 22580421120
19 81188953600
20 291176175104
21 1041867493376
22 3720118018048
23 13257657264128