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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 40 |
| 3 | 367 |
| 4 | 3024 |
| 5 | 24367 |
| 6 | 194128 |
| 7 | 1541546 |
| 8 | 12227770 |
| 9 | 96959431 |
| 10 | 768753274 |
| 11 | 6094924742 |
| 12 | 48322123369 |
| 13 | 383109017517 |
| 14 | 3037374726727 |
| 15 | 24080986205238 |
| 16 | 190919430801596 |
| 17 | 1513651808020772 |
| 18 | 12000568887531905 |
| 19 | 95143184583328459 |
[4,40,367,3024,24367,194128,1541546,12227770, 96959431,768753274,6094924742,48322123369, 383109017517,3037374726727,24080986205238, 190919430801596,1513651808020772, 12000568887531905,95143184583328459] |