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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 25 |
| 5 | 57 |
| 6 | 145 |
| 7 | 337 |
| 8 | 793 |
| 9 | 1921 |
| 10 | 3849 |
| 11 | 8835 |
| 12 | 18889 |
| 13 | 41473 |
| 14 | 92305 |
| 15 | 203211 |
| 16 | 432699 |
| 17 | 944313 |
| 18 | 2027529 |
| 19 | 4077769 |
| 20 | 8745153 |
| 21 | 18133305 |
| 22 | 37898113 |
| 23 | 80713737 |
| 24 | 169730259 |
| 25 | 358760457 |
| 26 | 750591867 |
| 27 | 1575313473 |
| 28 | 3255787851 |
| 29 | 6751959507 |
| 30 | 14108682265 |
| 31 | 29364255033 |
| 32 | 61173205587 |
[1,3,9,25,57,145,337,793,1921,3849,8835,18889, 41473,92305,203211,432699,944313,2027529,4077769, 8745153,18133305,37898113,80713737,169730259, 358760457,750591867,1575313473,3255787851, 6751959507,14108682265,29364255033,61173205587] |