The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 45 |
| 4 | 225 |
| 5 | 1125 |
| 6 | 5625 |
| 7 | 28125 |
| 8 | 140625 |
| 9 | 703125 |
| 10 | 3515625 |
| 11 | 17578125 |
| 12 | 87890625 |
| 13 | 439453125 |
| 14 | 2197265625 |
| 15 | 10986328125 |
| 16 | 54931640625 |
| 17 | 274658203125 |
| 18 | 1373291015625 |
| 19 | 6866455078125 |
| 20 | 34332275390625 |
| 21 | 171661376953125 |
| 22 | 858306884765625 |
| 23 | 4291534423828125 |
| 24 | 21457672119140625 |
[1,9,45,225,1125,5625,28125,140625,703125,3515625, 17578125,87890625,439453125,2197265625, 10986328125,54931640625,274658203125, 1373291015625,6866455078125,34332275390625, 171661376953125,858306884765625,4291534423828125, 21457672119140625] |