n | a(n) |
---|---|
1 | 1 |
2 | 4 |
3 | 15 |
4 | 87 |
5 | 1054 |
6 | 21214 |
7 | 649029 |
8 | 33757130 |
9 | 2831764125 |
10 | 388624884126 |
11 | 87386482775870 |
12 | 32119546783363536 |
13 | 19300894647086693888 |
[1,4,15,87,1054,21214,649029,33757130,2831764125, 388624884126,87386482775870,32119546783363536, 19300894647086693888] |