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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 6 |
| 4 | 11 |
| 5 | 26 |
| 6 | 63 |
| 7 | 158 |
| 8 | 411 |
| 9 | 1098 |
| 10 | 2955 |
| 11 | 8054 |
| 12 | 22151 |
| 13 | 61322 |
| 14 | 170823 |
| 15 | 478318 |
| 16 | 1345211 |
| 17 | 3798242 |
| 18 | 10761723 |
| 19 | 30585830 |
| 20 | 87169619 |
| 21 | 249056138 |
| 22 | 713205903 |
| 23 | 2046590846 |
| 24 | 5883948951 |
| 25 | 16945772210 |
| 26 | 48882035163 |
| 27 | 141214768974 |
[2,3,6,11,26,63,158,411,1098,2955,8054,22151, 61322,170823,478318,1345211,3798242,10761723, 30585830,87169619,249056138,713205903,2046590846, 5883948951,16945772210,48882035163,141214768974] |