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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 2 |
| 8 | 1 |
| 9 | 4 |
| 10 | 1 |
| 11 | 9 |
| 12 | 3 |
| 13 | 31 |
| 14 | 9 |
| 15 | 123 |
| 16 | 22 |
| 17 | 539 |
| 18 | 75 |
| 19 | 3348 |
| 20 | 380 |
| 21 | 26210 |
| 22 | 2417 |
| 23 | 248376 |
| 24 | 17011 |
| 25 | 2847301 |
| 26 | 150387 |
| 27 | 41349456 |
| 28 | 1725197 |
| 29 | 766696111 |
| 30 | 24767029 |
[1,1,1,1,1,1,2,1,4,1,9,3,31,9,123,22,539,75,3348, 380,26210,2417,248376,17011,2847301,150387, 41349456,1725197,766696111,24767029] |