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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 31 |
| 5 | 131 |
| 6 | 2127 |
| 7 | 2258 |
| 8 | 22449 |
| 9 | 47156 |
| 10 | 69605 |
| 11 | 882416 |
| 12 | 4481685 |
| 13 | 5364101 |
| 14 | 9845786 |
| 15 | 15209887 |
| 16 | 40265560 |
| 17 | 55475447 |
| 18 | 206691901 |
| 19 | 262167348 |
| 20 | 468859249 |
| 21 | 1668745095 |
| 22 | 2137604344 |
| 23 | 5943953783 |
| 24 | 8081558127 |
| 25 | 14025511910 |
| 26 | 22107070037 |
| 27 | 124560862095 |
| 28 | 1516837415177 |
[1,1,3,7,31,131,2127,2258,22449,47156,69605, 882416,4481685,5364101,9845786,15209887,40265560, 55475447,206691901,262167348,468859249,1668745095, 2137604344,5943953783,8081558127,14025511910, 22107070037,124560862095,1516837415177] |