# A094253 (b-file synthesized from sequence entry)
1 1
2 8
3 20
4 120
5 496
6 2304
7 10240
8 46208
9 207360
10 932352
11 4189184
12 18827264
13 84606976
14 380223488
15 1708703744
16 7678853120
17 34508439552
18 155079540736
19 696921096192
20 3131935031296
21 14074788184064
22 63251524091904