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| n | a(n) |
|---|---|
| 0 | -4 |
| 1 | -2 |
| 2 | 4 |
| 3 | 22 |
| 4 | 76 |
| 5 | 238 |
| 6 | 724 |
| 7 | 2182 |
| 8 | 6556 |
| 9 | 19678 |
| 10 | 59044 |
| 11 | 177142 |
| 12 | 531436 |
| 13 | 1594318 |
| 14 | 4782964 |
| 15 | 14348902 |
| 16 | 43046716 |
| 17 | 129140158 |
| 18 | 387420484 |
| 19 | 1162261462 |
| 20 | 3486784396 |
| 21 | 10460353198 |
| 22 | 31381059604 |
| 23 | 94143178822 |
| 24 | 282429536476 |
| 25 | 847288609438 |
[-4,-2,4,22,76,238,724,2182,6556,19678,59044, 177142,531436,1594318,4782964,14348902,43046716, 129140158,387420484,1162261462,3486784396, 10460353198,31381059604,94143178822,282429536476, 847288609438] |