# A012771 (b-file synthesized from sequence entry)
0 1
1 1
2 1
3 3
4 9
5 25
6 105
7 371
8 1393
9 11985
10 71025
11 -13981
12 -898887
13 45127017
14 455252889
15 -5553908333
16 -75822681503
17 1415759895841
18 21366754787169
19 -404022487469117
20 -7036035942040855
21 148035510590478137