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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 1 |
| 3 | 1 |
| 4 | 4 |
| 5 | 3 |
| 6 | 5 |
| 7 | 10 |
| 8 | 9 |
| 9 | 15 |
| 10 | 40 |
| 11 | 41 |
| 12 | 65 |
| 13 | 162 |
| 14 | 189 |
| 15 | 321 |
| 16 | 780 |
| 17 | 919 |
| 18 | 1681 |
| 19 | 4034 |
| 20 | 5281 |
| 21 | 9259 |
| 22 | 23936 |
| 23 | 30665 |
| 24 | 57601 |
| 25 | 143602 |
| 26 | 199577 |
| 27 | 367561 |
| 28 | 959236 |
| 29 | 1323243 |
| 30 | 2585133 |
| 31 | 6580650 |
| 32 | 9609145 |
| 33 | 18433799 |
| 34 | 49030248 |
| 35 | 71211721 |
| 36 | 142636377 |
| 37 | 371147842 |
| 38 | 566921925 |
| 39 | 1122881889 |
| 40 | 3024341084 |
| 41 | 4583822647 |
| 42 | 9446124313 |
[2,1,1,4,3,5,10,9,15,40,41,65,162,189,321,780,919, 1681,4034,5281,9259,23936,30665,57601,143602, 199577,367561,959236,1323243,2585133,6580650, 9609145,18433799,49030248,71211721,142636377, 371147842,566921925,1122881889,3024341084, 4583822647,9446124313] |