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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 57 |
| 3 | 205 |
| 4 | 733 |
| 5 | 2627 |
| 6 | 9305 |
| 7 | 32576 |
| 8 | 113448 |
| 9 | 394406 |
| 10 | 1369551 |
| 11 | 4750768 |
| 12 | 16468347 |
| 13 | 57064823 |
| 14 | 197691644 |
| 15 | 684764755 |
| 16 | 2371639753 |
| 17 | 8213463074 |
| 18 | 28443621204 |
| 19 | 98498816070 |
| 20 | 341089856906 |
| 21 | 1181139073972 |
| 22 | 4090059069992 |
| 23 | 14163013655470 |
[13,57,205,733,2627,9305,32576,113448,394406, 1369551,4750768,16468347,57064823,197691644, 684764755,2371639753,8213463074,28443621204, 98498816070,341089856906,1181139073972, 4090059069992,14163013655470] |