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| n | a(n) |
|---|---|
| 3 | 1 |
| 4 | 2 |
| 5 | 2 |
| 6 | 7 |
| 7 | 14 |
| 8 | 53 |
| 9 | 171 |
| 10 | 691 |
| 11 | 2738 |
| 12 | 11720 |
| 13 | 50486 |
| 14 | 224012 |
| 15 | 1005468 |
| 16 | 4581815 |
| 17 | 21093190 |
| 18 | 98093226 |
| 19 | 459986674 |
| 20 | 2173599817 |
| 21 | 10340539744 |
| 22 | 49496519950 |
| 23 | 238240366274 |
| 24 | 1152543685463 |
| 25 | 5601603835982 |
| 26 | 27341242042238 |
| 27 | 133977037982121 |
| 28 | 658902522544060 |
| 29 | 3251446102879398 |
[1,2,2,7,14,53,171,691,2738,11720,50486,224012, 1005468,4581815,21093190,98093226,459986674, 2173599817,10340539744,49496519950,238240366274, 1152543685463,5601603835982,27341242042238, 133977037982121,658902522544060,3251446102879398] |