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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 57 |
| 3 | 453 |
| 4 | 3617 |
| 5 | 28888 |
| 6 | 230726 |
| 7 | 1842766 |
| 8 | 14717828 |
| 9 | 117548611 |
| 10 | 938839259 |
| 11 | 7498337380 |
| 12 | 59887849061 |
| 13 | 478313295496 |
| 14 | 3820200795065 |
| 15 | 30511244937310 |
| 16 | 243687732023270 |
| 17 | 1946289338913085 |
| 18 | 15544656923507264 |
| 19 | 124152331330394548 |
[7,57,453,3617,28888,230726,1842766,14717828, 117548611,938839259,7498337380,59887849061, 478313295496,3820200795065,30511244937310, 243687732023270,1946289338913085, 15544656923507264,124152331330394548] |