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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 55 |
| 3 | 322 |
| 4 | 1953 |
| 5 | 11619 |
| 6 | 70044 |
| 7 | 418925 |
| 8 | 2518389 |
| 9 | 15091626 |
| 10 | 90619253 |
| 11 | 543451183 |
| 12 | 3261698460 |
| 13 | 19566441353 |
| 14 | 117412757177 |
| 15 | 704423288546 |
| 16 | 4226740369841 |
| 17 | 25359685459275 |
| 18 | 152160965127516 |
| 19 | 912955035168789 |
| 20 | 5477770757446957 |
[9,55,322,1953,11619,70044,418925,2518389, 15091626,90619253,543451183,3261698460, 19566441353,117412757177,704423288546, 4226740369841,25359685459275,152160965127516, 912955035168789,5477770757446957] |