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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 33 |
| 5 | 114 |
| 6 | 439 |
| 7 | 1689 |
| 8 | 6816 |
| 9 | 27624 |
| 10 | 114988 |
| 11 | 482122 |
| 12 | 2052197 |
| 13 | 8800591 |
| 14 | 38111226 |
| 15 | 166113251 |
| 16 | 729043557 |
| 17 | 3217041687 |
| 18 | 14269984543 |
| 19 | 63581058548 |
| 20 | 284464187518 |
| 21 | 1277397712864 |
| 22 | 5755627288014 |
| 23 | 26013095364631 |
| 24 | 117900835435171 |
| 25 | 535755079557245 |
| 26 | 2440363785685090 |
| 27 | 11140458053301700 |
| 28 | 50961594352233542 |
[1,1,3,9,33,114,439,1689,6816,27624,114988,482122, 2052197,8800591,38111226,166113251,729043557, 3217041687,14269984543,63581058548,284464187518, 1277397712864,5755627288014,26013095364631, 117900835435171,535755079557245,2440363785685090, 11140458053301700,50961594352233542] |