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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 8 |
| 2 | 30 |
| 3 | 122 |
| 4 | 548 |
| 5 | 2802 |
| 6 | 15638 |
| 7 | 100760 |
| 8 | 661242 |
| 9 | 5519558 |
| 10 | 36021212 |
| 11 | 495019758 |
| 12 | 944742290 |
| 13 | 96695115272 |
| 14 | -1151063332242 |
| 15 | 46492769525882 |
| 16 | -1177828529162332 |
| 17 | 39211350154011570 |
| 18 | -1272035779868081338 |
| 19 | 45289997660347946648 |
| 20 | -1679496857400789295638 |
| 21 | 65976928289858329056518 |
[2,8,30,122,548,2802,15638,100760,661242,5519558, 36021212,495019758,944742290,96695115272, -1151063332242,46492769525882,-1177828529162332, 39211350154011570,-1272035779868081338, 45289997660347946648,-1679496857400789295638, 65976928289858329056518] |