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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 6 |
| 7 | 1 |
| 8 | 20 |
| 9 | 13 |
| 10 | 138 |
| 11 | 69 |
| 12 | 1792 |
| 13 | 528 |
| 14 | 26977 |
| 15 | 7033 |
| 16 | 655185 |
| 17 | 141904 |
| 18 | 24548006 |
| 19 | 4322355 |
| 20 | 1409242126 |
| 21 | 197401178 |
| 22 | 123270232283 |
| 23 | 13868215311 |
| 24 | 16071746508178 |
| 25 | 1479290583806 |
| 26 | 3212023185510693 |
[1,1,1,1,1,6,1,20,13,138,69,1792,528,26977,7033, 655185,141904,24548006,4322355,1409242126, 197401178,123270232283,13868215311,16071746508178, 1479290583806,3212023185510693] |