# A018249 (b-file synthesized from sequence entry)
0 1
1 2
2 6
3 18
4 52
5 130
6 310
7 718
8 1618
9 3670
10 8160
11 17862
12 38872
13 84016
14 180502
15 386092
16 821640
17 1742536
18 3681130
19 7754076
20 16290046
21 34136028
22 71378568
23 148948138
24 310248240
25 645155196
26 1339484196
27 2777105128
28 5750079046