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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 2 |
| 6 | 1 |
| 7 | 13 |
| 8 | 26 |
| 9 | 7 |
| 10 | 1 |
| 11 | 40 |
| 12 | 260 |
| 13 | 280 |
| 14 | 47 |
| 15 | 1 |
| 16 | 121 |
| 17 | 2420 |
| 18 | 8470 |
| 19 | 5687 |
| 20 | 628 |
[1,1,1,1,4,2,1,13,26,7,1,40,260,280,47,1,121,2420, 8470,5687,628] |