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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 80 |
| 3 | 496 |
| 4 | 1557 |
| 5 | 6898 |
| 6 | 13504 |
| 7 | 34624 |
| 8 | 70093 |
| 9 | 148847 |
| 10 | 228892 |
| 11 | 445746 |
| 12 | 634828 |
| 13 | 1050561 |
| 14 | 1577663 |
| 15 | 2454082 |
| 16 | 3224498 |
| 17 | 5045974 |
| 18 | 6413426 |
| 19 | 9283270 |
| 20 | 12331470 |
| 21 | 16833674 |
| 22 | 20503929 |
| 23 | 28478040 |
| 24 | 35893071 |
| 25 | 46651077 |
| 26 | 57687196 |
| 27 | 73435900 |
| 28 | 85766121 |
[9,80,496,1557,6898,13504,34624,70093,148847, 228892,445746,634828,1050561,1577663,2454082, 3224498,5045974,6413426,9283270,12331470,16833674, 20503929,28478040,35893071,46651077,57687196, 73435900,85766121] |