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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 13 |
| 4 | 49 |
| 5 | 161 |
| 6 | 581 |
| 7 | 2045 |
| 8 | 7393 |
| 9 | 26689 |
| 10 | 97285 |
| 11 | 355565 |
| 12 | 1305745 |
| 13 | 4808545 |
| 14 | 17760965 |
| 15 | 65753693 |
| 16 | 243954113 |
| 17 | 906758785 |
| 18 | 3375949829 |
| 19 | 12587460557 |
| 20 | 46995614449 |
| 21 | 175669746209 |
| 22 | 657370655045 |
| 23 | 2462383495357 |
| 24 | 9232029156001 |
[1,1,5,13,49,161,581,2045,7393,26689,97285,355565, 1305745,4808545,17760965,65753693,243954113, 906758785,3375949829,12587460557,46995614449, 175669746209,657370655045,2462383495357, 9232029156001] |