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| n | a(n) |
|---|---|
| 1 | 81 |
| 2 | 549 |
| 3 | 549 |
| 4 | 3459 |
| 5 | 8160 |
| 6 | 3459 |
| 7 | 20537 |
| 8 | 112146 |
| 9 | 110923 |
| 10 | 20537 |
| 11 | 118383 |
| 12 | 1403872 |
| 13 | 3294824 |
| 14 | 1378463 |
| 15 | 118383 |
| 16 | 668041 |
| 17 | 16791083 |
| 18 | 87473420 |
| 19 | 87276535 |
| 20 | 16385455 |
| 21 | 668041 |
| 22 | 3720671 |
| 23 | 193298612 |
| 24 | 2193348247 |
| 25 | 4948377018 |
| 26 | 2183863895 |
| 27 | 187651928 |
[81,549,549,3459,8160,3459,20537,112146,110923, 20537,118383,1403872,3294824,1378463,118383, 668041,16791083,87473420,87276535,16385455,668041, 3720671,193298612,2193348247,4948377018, 2183863895,187651928] |