# A085819 (b-file synthesized from sequence entry)
1 1
2 2
3 6
4 12
5 60
6 420
7 4620
8 9240
9 27720
10 360360
11 6126120
12 116396280
13 2677114440
14 77636318760
15 2406725881560
16 4813451763120
17 178097715235440
18 7302006324653040
19 313986271960080720
20 14757354782123793840