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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 22 |
| 5 | 87 |
| 6 | 377 |
| 7 | 1771 |
| 8 | 9026 |
| 9 | 49199 |
| 10 | 284983 |
| 11 | 1745336 |
| 12 | 11246563 |
| 13 | 75956728 |
| 14 | 535909242 |
| 15 | 3938660615 |
| 16 | 30078439304 |
| 17 | 238154159543 |
| 18 | 1951238032473 |
| 19 | 16514089454284 |
| 20 | 144148618179948 |
| 21 | 1295871420550063 |
| 22 | 11982543274136961 |
| 23 | 113830968212019730 |
| 24 | 1109755421437926323 |
| 25 | 11092205946446644962 |
| 26 | 113562177701272805808 |
| 27 | 1189885690276586123039 |
| 28 | 12749384941695403919951 |
| 29 | 139593699183914764551501 |
| 30 | 1560760177586802637547293 |
[1,1,2,7,22,87,377,1771,9026,49199,284983,1745336, 11246563,75956728,535909242,3938660615, 30078439304,238154159543,1951238032473, 16514089454284,144148618179948,1295871420550063, 11982543274136961,113830968212019730, 1109755421437926323,11092205946446644962, 113562177701272805808,1189885690276586123039, 12749384941695403919951,139593699183914764551501, 1560760177586802637547293] |