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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 86 |
| 3 | 330 |
| 4 | 2373 |
| 5 | 13954 |
| 6 | 88308 |
| 7 | 546357 |
| 8 | 3395402 |
| 9 | 21113828 |
| 10 | 131172423 |
| 11 | 815495131 |
| 12 | 5068082120 |
| 13 | 31501875273 |
| 14 | 195796100483 |
| 15 | 1216969262017 |
| 16 | 7564039441124 |
| 17 | 47014056913283 |
| 18 | 292214759342258 |
| 19 | 1816252628655892 |
| 20 | 11288871528329054 |
[2,86,330,2373,13954,88308,546357,3395402, 21113828,131172423,815495131,5068082120, 31501875273,195796100483,1216969262017, 7564039441124,47014056913283,292214759342258, 1816252628655892,11288871528329054] |