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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 603 |
| 4 | 3907 |
| 5 | 15373 |
| 6 | 46341 |
| 7 | 117271 |
| 8 | 261703 |
| 9 | 530937 |
| 10 | 999433 |
| 11 | 1770931 |
| 12 | 2985291 |
| 13 | 4826053 |
| 14 | 7528717 |
| 15 | 11389743 |
| 16 | 16776271 |
| 17 | 24136561 |
| 18 | 34011153 |
| 19 | 47044747 |
| 20 | 63998803 |
| 21 | 85764861 |
| 22 | 113378581 |
| 23 | 148034503 |
| 24 | 191101527 |
| 25 | 244139113 |
| 26 | 308914201 |
| 27 | 387418851 |
[1,1,603,3907,15373,46341,117271,261703,530937, 999433,1770931,2985291,4826053,7528717,11389743, 16776271,24136561,34011153,47044747,63998803, 85764861,113378581,148034503,191101527,244139113, 308914201,387418851] |