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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 11 |
| 5 | 17 |
| 6 | 44 |
| 7 | 74 |
| 8 | 184 |
| 9 | 327 |
| 10 | 790 |
| 11 | 1461 |
| 12 | 3452 |
| 13 | 6584 |
| 14 | 15278 |
| 15 | 29879 |
| 16 | 68290 |
| 17 | 136391 |
| 18 | 307696 |
| 19 | 625731 |
| 20 | 1395696 |
| 21 | 2883357 |
| 22 | 6367199 |
| 23 | 13338421 |
| 24 | 29193025 |
| 25 | 61920497 |
| 26 | 134442102 |
| 27 | 288368511 |
| 28 | 621609060 |
| 29 | 1346873365 |
| 30 | 2884432810 |
[1,1,3,4,11,17,44,74,184,327,790,1461,3452,6584, 15278,29879,68290,136391,307696,625731,1395696, 2883357,6367199,13338421,29193025,61920497, 134442102,288368511,621609060,1346873365, 2884432810] |