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| n | a(n) |
|---|---|
| 9 | 1 |
| 10 | 1 |
| 11 | 3 |
| 12 | 6 |
| 13 | 15 |
| 14 | 31 |
| 15 | 74 |
| 16 | 159 |
| 17 | 365 |
| 18 | 803 |
| 19 | 1813 |
| 20 | 4022 |
| 21 | 9038 |
| 22 | 20128 |
| 23 | 45093 |
| 24 | 100656 |
| 25 | 225263 |
| 26 | 503320 |
| 27 | 1126045 |
| 28 | 2517487 |
| 29 | 5631913 |
| 30 | 12596046 |
| 31 | 28181168 |
| 32 | 63045684 |
| 33 | 141071758 |
| 34 | 315668674 |
| 35 | 706452161 |
| 36 | 1581088178 |
| 37 | 3538954508 |
| 38 | 7921759060 |
| 39 | 17733983146 |
| 40 | 39702719910 |
| 41 | 88893039358 |
[1,1,3,6,15,31,74,159,365,803,1813,4022,9038, 20128,45093,100656,225263,503320,1126045,2517487, 5631913,12596046,28181168,63045684,141071758, 315668674,706452161,1581088178,3538954508, 7921759060,17733983146,39702719910,88893039358] |