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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 12 |
| 3 | 90 |
| 4 | 508 |
| 5 | 2391 |
| 6 | 9828 |
| 7 | 36428 |
| 8 | 124188 |
| 9 | 395199 |
| 10 | 1186344 |
| 11 | 3387252 |
| 12 | 9257364 |
| 13 | 24343037 |
| 14 | 61848096 |
| 15 | 152356032 |
| 16 | 364959196 |
| 17 | 852243948 |
| 18 | 1944226476 |
| 19 | 4341094220 |
| 20 | 9502198728 |
| 21 | 20419293123 |
| 22 | 43131708720 |
| 23 | 89656112256 |
| 24 | 183580652340 |
[1,12,90,508,2391,9828,36428,124188,395199, 1186344,3387252,9257364,24343037,61848096, 152356032,364959196,852243948,1944226476, 4341094220,9502198728,20419293123,43131708720, 89656112256,183580652340] |