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| n | a(n) |
|---|---|
| 1 | 28 |
| 2 | 86 |
| 3 | 628 |
| 4 | 2058 |
| 5 | 9310 |
| 6 | 25298 |
| 7 | 73220 |
| 8 | 126168 |
| 9 | 357238 |
| 10 | 423828 |
| 11 | 882418 |
| 12 | 1132550 |
| 13 | 1954860 |
| 14 | 2371648 |
| 15 | 2600598 |
| 16 | 3968188 |
| 17 | 4627280 |
| 18 | 6585390 |
| 19 | 7501858 |
| 20 | 10156328 |
| 21 | 14088548 |
| 22 | 24754940 |
| 23 | 26936208 |
| 24 | 32941678 |
| 25 | 47503218 |
| 26 | 61839490 |
| 27 | 72120200 |
[28,86,628,2058,9310,25298,73220,126168,357238, 423828,882418,1132550,1954860,2371648,2600598, 3968188,4627280,6585390,7501858,10156328,14088548, 24754940,26936208,32941678,47503218,61839490, 72120200] |