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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 8 |
| 3 | 19 |
| 4 | 41 |
| 5 | 84 |
| 6 | 171 |
| 7 | 347 |
| 8 | 690 |
| 9 | 1385 |
| 10 | 2825 |
| 11 | 5438 |
| 12 | 11077 |
| 13 | 24535 |
| 14 | 33720 |
| 15 | 102623 |
| 16 | 350605 |
| 17 | -1120228 |
| 18 | 5876775 |
| 19 | 11232063 |
| 20 | -256532422 |
| 21 | 1748895117 |
| 22 | -4057110163 |
| 23 | -42841409122 |
| 24 | 605093026361 |
| 25 | -3691581277925 |
| 26 | 3538657621384 |
| 27 | 186391745956155 |
| 28 | -2296017574506751 |
[1,3,8,19,41,84,171,347,690,1385,2825,5438,11077, 24535,33720,102623,350605,-1120228,5876775, 11232063,-256532422,1748895117,-4057110163, -42841409122,605093026361,-3691581277925, 3538657621384,186391745956155,-2296017574506751] |