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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 39 |
| 5 | 141 |
| 6 | 519 |
| 7 | 1933 |
| 8 | 7263 |
| 9 | 27479 |
| 10 | 104543 |
| 11 | 399543 |
| 12 | 1532779 |
| 13 | 5899167 |
| 14 | 22766607 |
| 15 | 88073091 |
| 16 | 341425551 |
| 17 | 1326019653 |
| 18 | 5158412943 |
| 19 | 20096457549 |
| 20 | 78396460299 |
| 21 | 306190920837 |
| 22 | 1197181197567 |
| 23 | 4685523856881 |
| 24 | 18354865147011 |
| 25 | 71962695111841 |
| 26 | 282357198103815 |
[1,1,3,11,39,141,519,1933,7263,27479,104543, 399543,1532779,5899167,22766607,88073091, 341425551,1326019653,5158412943,20096457549, 78396460299,306190920837,1197181197567, 4685523856881,18354865147011,71962695111841, 282357198103815] |