# A006755 (b-file synthesized from sequence entry)
0 0
1 2
2 3
3 4
4 8
5 14
6 25
7 47
8 86
9 164
10 314
11 603
12 1159
13 2271
14 4456
15 8748
16 17182
17 33761
18 66919
19 132679
20 263087