# A031506 (b-file synthesized from sequence entry)
0 1
1 4
2 13
3 36
4 96
5 253
6 664
7 1740
8 4557
9 11932
10 31240
11 81789
12 214128
13 560596
14 1467661
15 3842388
16 10059504
17 26336125
18 68948872
19 180510492
20 472582605
21 1237237324
22 3239129368
23 8480150781
24 22201322976