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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 10 |
| 3 | 19 |
| 4 | 56 |
| 5 | 155 |
| 6 | 313 |
| 7 | 851 |
| 8 | 2147 |
| 9 | 5513 |
| 10 | 14288 |
| 11 | 37168 |
| 12 | 97738 |
| 13 | 256043 |
| 14 | 672477 |
| 15 | 1769569 |
| 16 | 4660622 |
| 17 | 12294064 |
| 18 | 32431038 |
| 19 | 85627690 |
| 20 | 226117938 |
| 21 | 597377797 |
| 22 | 1578473210 |
| 23 | 4171676388 |
| 24 | 11026596808 |
| 25 | 29148466909 |
| 26 | 77059555630 |
| 27 | 203733482276 |
[2,10,19,56,155,313,851,2147,5513,14288,37168, 97738,256043,672477,1769569,4660622,12294064, 32431038,85627690,226117938,597377797,1578473210, 4171676388,11026596808,29148466909,77059555630, 203733482276] |