# A067648 (b-file synthesized from sequence entry)
0 0
1 2
2 0
3 2
4 4
5 12
6 60
7 226
8 1076
9 5156
10 24984
11 128548
12 663040
13 3514968
14 18918792
15 103123906
16 569877652
17 3180066004
18 17921451960
19 101842206548
20 583109887600
21 3361640932872
22 19499226668816