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| n | a(n) |
|---|---|
| 2 | 181 |
| 3 | 1637 |
| 4 | 7811 |
| 5 | 26659 |
| 6 | 73529 |
| 7 | 174761 |
| 8 | 372007 |
| 9 | 727271 |
| 10 | 1328669 |
| 11 | 2296909 |
| 12 | 3792491 |
| 13 | 6023627 |
| 14 | 9254881 |
| 15 | 13816529 |
| 16 | 20114639 |
| 17 | 28641871 |
| 18 | 39988997 |
| 19 | 54857141 |
| 20 | 74070739 |
| 21 | 98591219 |
| 22 | 129531401 |
| 23 | 168170617 |
| 24 | 215970551 |
| 25 | 274591799 |
| 26 | 345911149 |
[181,1637,7811,26659,73529,174761,372007,727271, 1328669,2296909,3792491,6023627,9254881,13816529, 20114639,28641871,39988997,54857141,74070739, 98591219,129531401,168170617,215970551,274591799, 345911149] |