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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 26 |
| 3 | 47 |
| 4 | 213 |
| 5 | 1109 |
| 6 | 5426 |
| 7 | 26626 |
| 8 | 133245 |
| 9 | 708063 |
| 10 | 3653857 |
| 11 | 18764147 |
| 12 | 97933770 |
| 13 | 509275871 |
| 14 | 2641581998 |
| 15 | 13734083323 |
| 16 | 71435032340 |
| 17 | 371258276206 |
| 18 | 1929981180495 |
| 19 | 10035489710904 |
| 20 | 52173575660786 |
| 21 | 271248632206329 |
| 22 | 1410301795143440 |
[1,26,47,213,1109,5426,26626,133245,708063, 3653857,18764147,97933770,509275871,2641581998, 13734083323,71435032340,371258276206, 1929981180495,10035489710904,52173575660786, 271248632206329,1410301795143440] |