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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 17 |
| 6 | 57 |
| 7 | 148 |
| 8 | 356 |
| 9 | 864 |
| 10 | 2272 |
| 11 | 5766 |
| 12 | 14438 |
| 13 | 36379 |
| 14 | 92632 |
| 15 | 234473 |
| 16 | 592300 |
| 17 | 1497878 |
| 18 | 3794198 |
| 19 | 9602820 |
| 20 | 24292985 |
| 21 | 61469034 |
| 22 | 155580439 |
| 23 | 393724501 |
| 24 | 996303601 |
| 25 | 2521217660 |
| 26 | 6380413994 |
| 27 | 16146453573 |
| 28 | 40860032492 |
| 29 | 103400766211 |
| 30 | 261668897174 |
[3,2,4,8,17,57,148,356,864,2272,5766,14438,36379, 92632,234473,592300,1497878,3794198,9602820, 24292985,61469034,155580439,393724501,996303601, 2521217660,6380413994,16146453573,40860032492, 103400766211,261668897174] |