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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 12 |
| 5 | 28 |
| 6 | 66 |
| 7 | 172 |
| 8 | 440 |
| 9 | 1108 |
| 10 | 2784 |
| 11 | 7552 |
| 12 | 20040 |
| 13 | 52336 |
| 14 | 136896 |
| 15 | 374688 |
| 16 | 1013056 |
| 17 | 2710016 |
| 18 | 7243104 |
| 19 | 20078784 |
| 20 | 55031040 |
| 21 | 149414144 |
| 22 | 405759232 |
| 23 | 1130565632 |
| 24 | 3125798656 |
| 25 | 8582582272 |
| 26 | 23543099392 |
| 27 | 66051398144 |
| 28 | 183922571264 |
| 29 | 508945206272 |
[1,2,5,12,28,66,172,440,1108,2784,7552,20040, 52336,136896,374688,1013056,2710016,7243104, 20078784,55031040,149414144,405759232,1130565632, 3125798656,8582582272,23543099392,66051398144, 183922571264,508945206272] |