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| n | a(n) |
|---|---|
| 1 | 68 |
| 2 | 156 |
| 3 | 318 |
| 4 | 604 |
| 5 | 1144 |
| 6 | 2108 |
| 7 | 3924 |
| 8 | 7236 |
| 9 | 13486 |
| 10 | 25108 |
| 11 | 47168 |
| 12 | 88856 |
| 13 | 168588 |
| 14 | 321220 |
| 15 | 615390 |
| 16 | 1184204 |
| 17 | 2288040 |
| 18 | 4438780 |
| 19 | 8636484 |
| 20 | 16862164 |
| 21 | 32990542 |
| 22 | 64729172 |
| 23 | 127184496 |
| 24 | 250474872 |
| 25 | 493763644 |
| 26 | 975154132 |
| 27 | 1927138430 |
| 28 | 3814135532 |
[68,156,318,604,1144,2108,3924,7236,13486,25108, 47168,88856,168588,321220,615390,1184204,2288040, 4438780,8636484,16862164,32990542,64729172, 127184496,250474872,493763644,975154132, 1927138430,3814135532] |