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| n | a(n) |
|---|---|
| 1 | 55 |
| 2 | 66 |
| 3 | 5050 |
| 4 | 5151 |
| 5 | 203203 |
| 6 | 255255 |
| 7 | 426426 |
| 8 | 500500 |
| 9 | 501501 |
| 10 | 581581 |
| 11 | 828828 |
| 12 | 930930 |
| 13 | 39653965 |
| 14 | 50005000 |
| 15 | 50015001 |
| 16 | 61566156 |
| 17 | 3347133471 |
| 18 | 5000050000 |
| 19 | 5000150001 |
| 20 | 6983669836 |
| 21 | 220028220028 |
| 22 | 500000500000 |
| 23 | 500001500001 |
[55,66,5050,5151,203203,255255,426426,500500, 501501,581581,828828,930930,39653965,50005000, 50015001,61566156,3347133471,5000050000, 5000150001,6983669836,220028220028,500000500000, 500001500001] |