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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 13 |
| 5 | 31 |
| 6 | 69 |
| 7 | 153 |
| 8 | 332 |
| 9 | 712 |
| 10 | 1509 |
| 11 | 3169 |
| 12 | 6603 |
| 13 | 13669 |
| 14 | 28142 |
| 15 | 57674 |
| 16 | 117741 |
| 17 | 239587 |
| 18 | 486193 |
| 19 | 984353 |
| 20 | 1989056 |
| 21 | 4012636 |
| 22 | 8083717 |
| 23 | 16266181 |
| 24 | 32698903 |
| 25 | 65678221 |
| 26 | 131827874 |
| 27 | 264447198 |
| 28 | 530221357 |
| 29 | 1062664807 |
| 30 | 2129046429 |
[1,1,2,6,13,31,69,153,332,712,1509,3169,6603, 13669,28142,57674,117741,239587,486193,984353, 1989056,4012636,8083717,16266181,32698903, 65678221,131827874,264447198,530221357,1062664807, 2129046429] |