# A124382 (b-file synthesized from sequence entry)
0 1
1 1
2 2
3 6
4 20
5 90
6 465
7 2826
8 20020
9 158348
10 1430189
11 14217275
12 157279196
13 1903617880
14 25151383277
15 361228405394
16 5594555181227
17 93472423847492
18 1671138501448565
19 31988293954710201
20 651665490924639449