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| n | a(n) |
|---|---|
| 1 | 2176 |
| 2 | 5641 |
| 3 | 15208 |
| 4 | 40756 |
| 5 | 137488 |
| 6 | 425816 |
| 7 | 1312020 |
| 8 | 4674588 |
| 9 | 14943406 |
| 10 | 47066756 |
| 11 | 170470012 |
| 12 | 547418472 |
| 13 | 1733138452 |
| 14 | 6310325660 |
| 15 | 20264448300 |
| 16 | 64210355548 |
| 17 | 234552267492 |
| 18 | 752373575104 |
| 19 | 2384156623940 |
| 20 | 8732484325388 |
| 21 | 27975783641552 |
[2176,5641,15208,40756,137488,425816,1312020, 4674588,14943406,47066756,170470012,547418472, 1733138452,6310325660,20264448300,64210355548, 234552267492,752373575104,2384156623940, 8732484325388,27975783641552] |