# A129997 (b-file synthesized from sequence entry)
1 0
2 1
3 4
4 14
5 52
6 208
7 884
8 3952
9 18460
10 89648
11 450892
12 2341456
13 12522068
14 68819920
15 387978292
16 2240112368
17 13228210684
18 79794191152
19 491143503500
20 3081692690128
21 19693923313012
22 128082776294096
23 847127801497588