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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 10 |
| 3 | 17 |
| 4 | 50 |
| 5 | 122 |
| 6 | 325 |
| 7 | 842 |
| 8 | 2210 |
| 9 | 5777 |
| 10 | 15130 |
| 11 | 39602 |
| 12 | 103685 |
| 13 | 271442 |
| 14 | 710650 |
| 15 | 1860497 |
| 16 | 4870850 |
| 17 | 12752042 |
| 18 | 33385285 |
| 19 | 87403802 |
| 20 | 228826130 |
| 21 | 599074577 |
| 22 | 1568397610 |
| 23 | 4106118242 |
| 24 | 10749957125 |
| 25 | 28143753122 |
| 26 | 73681302250 |
| 27 | 192900153617 |
| 28 | 505019158610 |
| 29 | 1322157322202 |
[2,10,17,50,122,325,842,2210,5777,15130,39602, 103685,271442,710650,1860497,4870850,12752042, 33385285,87403802,228826130,599074577,1568397610, 4106118242,10749957125,28143753122,73681302250, 192900153617,505019158610,1322157322202] |