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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 4 |
| 4 | 33 |
| 5 | 2468 |
| 6 | 25 |
| 7 | 176366 |
| 8 | 1697 |
| 9 | 13842 |
| 10 | 1379 |
| 11 | 11223344464 |
| 12 | 13093 |
| 13 | 949667608470093 |
| 14 | 9707938 |
| 15 | 8318740876 |
| 16 | 8486944572 |
| 17 | 7262164064771301847951 |
| 18 | 87284065 |
| 19 | 64977257421637963902716694 |
| 20 | 689555658595 |
| 21 | 5932429101505580572 |
[1,5,4,33,2468,25,176366,1697,13842,1379, 11223344464,13093,949667608470093,9707938, 8318740876,8486944572,7262164064771301847951, 87284065,64977257421637963902716694,689555658595, 5932429101505580572] |