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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 14 |
| 3 | 155 |
| 4 | 1172 |
| 5 | 6843 |
| 6 | 43538 |
| 7 | 318457 |
| 8 | 2223803 |
| 9 | 14185700 |
| 10 | 84670477 |
| 11 | 477808607 |
| 12 | 2577052118 |
| 13 | 13759255632 |
| 14 | 75251167843 |
| 15 | 418157757456 |
| 16 | 2267313716636 |
| 17 | 11616142299625 |
| 18 | 55909713312571 |
| 19 | 257522103127082 |
| 20 | 1182251998919171 |
| 21 | 5791219719115580 |
| 22 | 32715779086392723 |
[1,14,155,1172,6843,43538,318457,2223803,14185700, 84670477,477808607,2577052118,13759255632, 75251167843,418157757456,2267313716636, 11616142299625,55909713312571,257522103127082, 1182251998919171,5791219719115580, 32715779086392723] |