# A004142 (b-file synthesized from sequence entry)
0 0
1 1
2 10
3 57
4 260
5 1055
6 3990
7 14413
8 50440
9 172539
10 580250
11 1926089
12 6328140
13 20619703
14 66732190
15 214742085
16 687698960
17 2193154547
18 6968850210
19 22073006401
20 69714716500
21 219623377071
22 690291036710