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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 11 |
| 4 | 25 |
| 5 | 55 |
| 6 | 125 |
| 7 | 279 |
| 8 | 625 |
| 9 | 1397 |
| 10 | 3125 |
| 11 | 6987 |
| 12 | 15625 |
| 13 | 34938 |
| 14 | 78125 |
| 15 | 174692 |
| 16 | 390625 |
| 17 | 873464 |
| 18 | 1953125 |
| 19 | 4367320 |
| 20 | 9765625 |
| 21 | 21836601 |
| 22 | 48828125 |
| 23 | 109183006 |
| 24 | 244140625 |
| 25 | 545915033 |
| 26 | 1220703125 |
| 27 | 2729575167 |
[1,2,5,11,25,55,125,279,625,1397,3125,6987,15625, 34938,78125,174692,390625,873464,1953125,4367320, 9765625,21836601,48828125,109183006,244140625, 545915033,1220703125,2729575167] |