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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 25 |
| 4 | 140 |
| 5 | 625 |
| 6 | 3250 |
| 7 | 15625 |
| 8 | 78785 |
| 9 | 390950 |
| 10 | 1956250 |
| 11 | 9765625 |
| 12 | 48847250 |
| 13 | 244140625 |
| 14 | 1220781250 |
| 15 | 6103531250 |
| 16 | 30517978570 |
| 17 | 152587890625 |
| 18 | 762941486000 |
| 19 | 3814697265625 |
| 20 | 19073496181250 |
| 21 | 95367432031250 |
| 22 | 476837207031250 |
| 23 | 2384185791015625 |
| 24 | 11920929201625875 |
| 25 | 59604644775586250 |
[1,5,25,140,625,3250,15625,78785,390950,1956250, 9765625,48847250,244140625,1220781250,6103531250, 30517978570,152587890625,762941486000, 3814697265625,19073496181250,95367432031250, 476837207031250,2384185791015625, 11920929201625875,59604644775586250] |