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| n | a(n) |
|---|---|
| 0 | 132 |
| 1 | 420 |
| 2 | 996 |
| 3 | 2148 |
| 4 | 4452 |
| 5 | 9060 |
| 6 | 18276 |
| 7 | 36708 |
| 8 | 73572 |
| 9 | 147300 |
| 10 | 294756 |
| 11 | 589668 |
| 12 | 1179492 |
| 13 | 2359140 |
| 14 | 4718436 |
| 15 | 9437028 |
| 16 | 18874212 |
| 17 | 37748580 |
| 18 | 75497316 |
| 19 | 150994788 |
| 20 | 301989732 |
| 21 | 603979620 |
| 22 | 1207959396 |
| 23 | 2415918948 |
| 24 | 4831838052 |
| 25 | 9663676260 |
| 26 | 19327352676 |
| 27 | 38654705508 |
[132,420,996,2148,4452,9060,18276,36708,73572, 147300,294756,589668,1179492,2359140,4718436, 9437028,18874212,37748580,75497316,150994788, 301989732,603979620,1207959396,2415918948, 4831838052,9663676260,19327352676,38654705508] |