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| n | a(n) |
|---|---|
| 1 | 15 |
| 2 | 408 |
| 3 | 16838 |
| 4 | 167649 |
| 5 | 4140037 |
| 6 | 9474308 |
| 7 | 74874018 |
| 8 | 102945521 |
| 9 | 527810589 |
| 10 | 2859439915 |
| 11 | 2098740462 |
| 12 | 13633995047 |
| 13 | 19976100632 |
| 14 | 15333179080 |
| 15 | 46445400546 |
| 16 | 130987140051 |
| 17 | 255274374202 |
| 18 | 126415848050 |
| 19 | 560858856747 |
| 20 | 579824938579 |
| 21 | 371808136740 |
| 22 | 1546366165352 |
| 23 | 1496392986944 |
[15,408,16838,167649,4140037,9474308,74874018, 102945521,527810589,2859439915,2098740462, 13633995047,19976100632,15333179080,46445400546, 130987140051,255274374202,126415848050, 560858856747,579824938579,371808136740, 1546366165352,1496392986944] |