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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 8 |
| 7 | 6 |
| 8 | 11 |
| 9 | 21 |
| 10 | 51 |
| 11 | 11 |
| 12 | 22 |
| 13 | 133 |
| 14 | 159 |
| 15 | 151 |
| 16 | 328 |
| 17 | 707 |
| 18 | 1414 |
| 19 | 880 |
| 20 | 1732 |
| 21 | 3850 |
| 22 | 9482 |
| 23 | 1742 |
| 24 | 3480 |
| 25 | 22126 |
| 26 | 37243 |
| 27 | 25604 |
| 28 | 51381 |
| 29 | 102087 |
| 30 | 204174 |
| 31 | 157324 |
| 32 | 285010 |
| 33 | 660221 |
| 34 | 1285026 |
| 35 | 262885 |
| 36 | 547906 |
| 37 | 3664304 |
| 38 | 5844380 |
| 39 | 3927062 |
| 40 | 8543954 |
| 41 | 19956539 |
[1,1,1,2,4,8,6,11,21,51,11,22,133,159,151,328,707, 1414,880,1732,3850,9482,1742,3480,22126,37243, 25604,51381,102087,204174,157324,285010,660221, 1285026,262885,547906,3664304,5844380,3927062, 8543954,19956539] |