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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 5 |
| 4 | 144 |
| 5 | 149 |
| 6 | 591 |
| 7 | 740 |
| 8 | 21311 |
| 9 | 22051 |
| 10 | 87464 |
| 11 | 109515 |
| 12 | 3153884 |
| 13 | 3263399 |
| 14 | 12944081 |
| 15 | 16207480 |
| 16 | 466753521 |
| 17 | 482961001 |
| 18 | 1915636524 |
| 19 | 2398597525 |
| 20 | 69076367224 |
| 21 | 71474964749 |
| 22 | 283501261471 |
| 23 | 354976226220 |
| 24 | 10222835595631 |
| 25 | 10577811821851 |
| 26 | 41956271061184 |
[1,1,4,5,144,149,591,740,21311,22051,87464,109515, 3153884,3263399,12944081,16207480,466753521, 482961001,1915636524,2398597525,69076367224, 71474964749,283501261471,354976226220, 10222835595631,10577811821851,41956271061184] |