# A007508 (b-file synthesized from sequence entry)
1 2
2 8
3 35
4 205
5 1224
6 8169
7 58980
8 440312
9 3424506
10 27412679
11 224376048
12 1870585220
13 15834664872
14 135780321665
15 1177209242304
16 10304195697298
17 90948839353159
18 808675888577436