# A253096 (b-file synthesized from sequence entry)
0 1
1 5
2 35
3 305
4 3105
5 35505
6 444225
7 5970725
8 85068365
9 1272022745
10 19810304695
11 319422093325
12 5307057746125
13 90508769121165
14 1579462112057595
15 28130401719357645
16 510199561574590125
17 9405815167297415025
18 175977472926360962295
19 3336795660732459377085
20 64047222901288457886285