# A004077 (b-file synthesized from sequence entry)
1 2
2 2
3 6
4 22
5 48
6 160
7 636
8 3556
9 19488
10 95872
11 594320
12 4459888
13 32131648
14 227072544
15 1875064880
16 17851780784
17 165367171136
18 1506506453568
19 15540217445728
20 179708231523680
21 2034547787823488
22 22716589497430656