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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 8 |
| 2 | 23 |
| 3 | 61 |
| 4 | 160 |
| 5 | 419 |
| 6 | 1097 |
| 7 | 2872 |
| 8 | 7519 |
| 9 | 19685 |
| 10 | 51536 |
| 11 | 134923 |
| 12 | 353233 |
| 13 | 924776 |
| 14 | 2421095 |
| 15 | 6338509 |
| 16 | 16594432 |
| 17 | 43444787 |
| 18 | 113739929 |
| 19 | 297775000 |
| 20 | 779585071 |
| 21 | 2040980213 |
| 22 | 5343355568 |
| 23 | 13989086491 |
| 24 | 36623903905 |
| 25 | 95882625224 |
| 26 | 251023971767 |
| 27 | 657189290077 |
| 28 | 1720543898464 |
[1,8,23,61,160,419,1097,2872,7519,19685,51536, 134923,353233,924776,2421095,6338509,16594432, 43444787,113739929,297775000,779585071,2040980213, 5343355568,13989086491,36623903905,95882625224, 251023971767,657189290077,1720543898464] |