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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 38 |
| 3 | 242 |
| 4 | 1802 |
| 5 | 7550 |
| 6 | 31412 |
| 7 | 100350 |
| 8 | 310079 |
| 9 | 811472 |
| 10 | 2065406 |
| 11 | 4695974 |
| 12 | 10458806 |
| 13 | 21370898 |
| 14 | 42897546 |
| 15 | 80938346 |
| 16 | 150245395 |
| 17 | 265231474 |
| 18 | 462690716 |
| 19 | 774729470 |
| 20 | 1283610082 |
| 21 | 2057355212 |
| 22 | 3266479406 |
| 23 | 5043183866 |
| 24 | 7727895633 |
| 25 | 11557992252 |
[2,38,242,1802,7550,31412,100350,310079,811472, 2065406,4695974,10458806,21370898,42897546, 80938346,150245395,265231474,462690716,774729470, 1283610082,2057355212,3266479406,5043183866, 7727895633,11557992252] |