n | a(n) |
---|---|
1 | 1 |
2 | 2 |
3 | 15 |
4 | 30 |
5 | 176 |
6 | 490 |
7 | 792 |
8 | 31185 |
9 | 831820 |
10 | 2323520 |
11 | 8118264 |
12 | 118114304 |
13 | 2841940500 |
14 | 3163127352 |
15 | 684957390936 |
16 | 60105349839666544 |
17 | 471314064268398780 |
18 | 52527070729108240605 |
19 | 57601805366500810491219000 |
20 | 23127843459154899464880444632250 |
[1,2,15,30,176,490,792,31185,831820,2323520, 8118264,118114304,2841940500,3163127352, 684957390936,60105349839666544,471314064268398780, 52527070729108240605,57601805366500810491219000, 23127843459154899464880444632250] |