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| n | a(n) |
|---|---|
| 1 | 22 |
| 2 | 89 |
| 3 | 304 |
| 4 | 1253 |
| 5 | 5109 |
| 6 | 21894 |
| 7 | 94234 |
| 8 | 411978 |
| 9 | 1804685 |
| 10 | 7941968 |
| 11 | 34969518 |
| 12 | 154177482 |
| 13 | 679856170 |
| 14 | 2999022193 |
| 15 | 13230140405 |
| 16 | 58371368067 |
| 17 | 257539346061 |
| 18 | 1136325839478 |
| 19 | 5013778949950 |
| 20 | 22122400344087 |
| 21 | 97611358054570 |
[22,89,304,1253,5109,21894,94234,411978,1804685, 7941968,34969518,154177482,679856170,2999022193, 13230140405,58371368067,257539346061, 1136325839478,5013778949950,22122400344087, 97611358054570] |