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| n | a(n) |
|---|---|
| 15 | 1 |
| 16 | 1 |
| 17 | 9 |
| 18 | 13 |
| 19 | 66 |
| 20 | 111 |
| 21 | 475 |
| 22 | 852 |
| 23 | 3128 |
| 24 | 5668 |
| 25 | 19011 |
| 26 | 34804 |
| 27 | 108328 |
| 28 | 195267 |
| 29 | 567674 |
| 30 | 1059291 |
| 31 | 2849122 |
| 32 | 5212695 |
| 33 | 13785287 |
| 34 | 25156313 |
| 35 | 62613272 |
| 36 | 115799409 |
| 37 | 277245609 |
| 38 | 508970856 |
| 39 | 1196118973 |
| 40 | 2161689541 |
[1,1,9,13,66,111,475,852,3128,5668,19011,34804, 108328,195267,567674,1059291,2849122,5212695, 13785287,25156313,62613272,115799409,277245609, 508970856,1196118973,2161689541] |