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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 9 |
| 6 | 13 |
| 7 | 20 |
| 8 | 38 |
| 9 | 71 |
| 10 | 119 |
| 11 | 206 |
| 12 | 384 |
| 13 | 713 |
| 14 | 1285 |
| 15 | 2356 |
| 16 | 4428 |
| 17 | 8331 |
| 18 | 15569 |
| 19 | 29270 |
| 20 | 55582 |
| 21 | 105717 |
| 22 | 200847 |
| 23 | 382808 |
| 24 | 732744 |
| 25 | 1404667 |
| 26 | 2694391 |
| 27 | 5178186 |
| 28 | 9973416 |
| 29 | 19233457 |
| 30 | 37125547 |
| 31 | 71754692 |
| 32 | 138871244 |
| 33 | 269038123 |
| 34 | 521666967 |
| 35 | 1012485750 |
| 36 | 1966957674 |
| 37 | 3824314685 |
[1,1,2,4,9,13,20,38,71,119,206,384,713,1285,2356, 4428,8331,15569,29270,55582,105717,200847,382808, 732744,1404667,2694391,5178186,9973416,19233457, 37125547,71754692,138871244,269038123,521666967, 1012485750,1966957674,3824314685] |