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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 1 |
| 6 | 15 |
| 7 | 1 |
| 8 | 41 |
| 9 | 23 |
| 10 | 133 |
| 11 | 1 |
| 12 | 650 |
| 13 | 1 |
| 14 | 1725 |
| 15 | 961 |
| 16 | 6930 |
| 17 | 1 |
| 18 | 30323 |
| 19 | 1 |
| 20 | 99716 |
| 21 | 40431 |
| 22 | 352729 |
| 23 | 1 |
| 24 | 1709125 |
| 25 | 35467 |
| 26 | 5200315 |
| 27 | 2008233 |
| 28 | 20960538 |
| 29 | 1 |
| 30 | 93058849 |
| 31 | 1 |
| 32 | 312220259 |
| 33 | 105533203 |
| 34 | 1166803129 |
| 35 | 20194059 |
| 36 | 5478229800 |
| 37 | 1 |
| 38 | 17672631921 |
| 39 | 5731781295 |
| 40 | 71539226243 |
| 41 | 1 |
[0,1,1,4,1,15,1,41,23,133,1,650,1,1725,961,6930,1, 30323,1,99716,40431,352729,1,1709125,35467, 5200315,2008233,20960538,1,93058849,1,312220259, 105533203,1166803129,20194059,5478229800,1, 17672631921,5731781295,71539226243,1] |