# A181121 (b-file synthesized from sequence entry)
1 2
2 3
3 12
4 15
5 70
6 840
7 1260
8 2772
9 30030
10 720720
11 765765
12 12932920
13 243374040
14 6692786100
15 40156716600
16 83181770100
17 2406725881560
18 144403552893600
19 148414762696200
20 5476504743489780
21 224275908542914800