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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 6 |
| 3 | 14 |
| 4 | 30 |
| 5 | 67 |
| 6 | 146 |
| 7 | 320 |
| 8 | 706 |
| 9 | 1550 |
| 10 | 3403 |
| 11 | 7481 |
| 12 | 16443 |
| 13 | 36131 |
| 14 | 79399 |
| 15 | 174500 |
| 16 | 383499 |
| 17 | 842796 |
| 18 | 1852205 |
| 19 | 4070612 |
| 20 | 8945988 |
| 21 | 19660603 |
| 22 | 43208249 |
| 23 | 94959144 |
| 24 | 208692464 |
| 25 | 458645240 |
| 26 | 1007969053 |
| 27 | 2215223460 |
| 28 | 4868418432 |
| 29 | 10699372182 |
| 30 | 23514119454 |
[3,6,14,30,67,146,320,706,1550,3403,7481,16443, 36131,79399,174500,383499,842796,1852205,4070612, 8945988,19660603,43208249,94959144,208692464, 458645240,1007969053,2215223460,4868418432, 10699372182,23514119454] |