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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 40 |
| 4 | 259 |
| 5 | 1727 |
| 6 | 11677 |
| 7 | 78887 |
| 8 | 532826 |
| 9 | 3599266 |
| 10 | 24313336 |
| 11 | 164238089 |
| 12 | 1109439854 |
| 13 | 7494345348 |
| 14 | 50624835011 |
| 15 | 341974359592 |
[1,5,40,259,1727,11677,78887,532826,3599266, 24313336,164238089,1109439854,7494345348, 50624835011,341974359592] |