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| n | a(n) |
|---|---|
| 1 | 15 |
| 2 | 45 |
| 3 | 377 |
| 4 | 2179 |
| 5 | 11395 |
| 6 | 62341 |
| 7 | 358480 |
| 8 | 2042977 |
| 9 | 11133454 |
| 10 | 57524941 |
| 11 | 283686403 |
| 12 | 1346514989 |
| 13 | 6179034469 |
| 14 | 27460498749 |
| 15 | 118362882158 |
| 16 | 495874680973 |
| 17 | 2023906766644 |
| 18 | 8063298364234 |
| 19 | 31401504048785 |
| 20 | 119663290195459 |
[15,45,377,2179,11395,62341,358480,2042977, 11133454,57524941,283686403,1346514989,6179034469, 27460498749,118362882158,495874680973, 2023906766644,8063298364234,31401504048785, 119663290195459] |