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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 11 |
| 5 | 48 |
| 6 | 107 |
| 7 | 155 |
| 8 | 572 |
| 9 | 3015 |
| 10 | 6602 |
| 11 | 16219 |
| 12 | 22821 |
| 13 | 39040 |
| 14 | 100901 |
| 15 | 139941 |
| 16 | 660665 |
| 17 | 4103931 |
| 18 | 12972458 |
| 19 | 30048847 |
| 20 | 43021305 |
| 21 | 116091457 |
| 22 | 159112762 |
| 23 | 911655267 |
| 24 | 6540699631 |
| 25 | 20533754160 |
| 26 | 47608207951 |
| 27 | 115750170062 |
| 28 | 394858718137 |
| 29 | 510608888199 |
| 30 | 905467606336 |
[1,3,4,11,48,107,155,572,3015,6602,16219,22821, 39040,100901,139941,660665,4103931,12972458, 30048847,43021305,116091457,159112762,911655267, 6540699631,20533754160,47608207951,115750170062, 394858718137,510608888199,905467606336] |