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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 171 |
| 5 | 175 |
| 6 | 521 |
| 7 | 696 |
| 8 | 29753 |
| 9 | 30449 |
| 10 | 90651 |
| 11 | 121100 |
| 12 | 5176851 |
| 13 | 5297951 |
| 14 | 15772753 |
| 15 | 21070704 |
| 16 | 900742321 |
| 17 | 921813025 |
| 18 | 2744368371 |
| 19 | 3666181396 |
| 20 | 156723987003 |
| 21 | 160390168399 |
| 22 | 477504323801 |
| 23 | 637894492200 |
| 24 | 27269072996201 |
| 25 | 27906967488401 |
| 26 | 83083007973003 |
[1,1,3,4,171,175,521,696,29753,30449,90651,121100, 5176851,5297951,15772753,21070704,900742321, 921813025,2744368371,3666181396,156723987003, 160390168399,477504323801,637894492200, 27269072996201,27906967488401,83083007973003] |