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| n | a(n) |
|---|---|
| 0 | 7 |
| 1 | 25 |
| 2 | 42 |
| 3 | 75 |
| 4 | 385 |
| 5 | 642 |
| 6 | 1155 |
| 7 | 2184 |
| 8 | 4233 |
| 9 | 8330 |
| 10 | 16523 |
| 11 | 98305 |
| 12 | 163842 |
| 13 | 294915 |
| 14 | 557064 |
| 15 | 1081353 |
| 16 | 2129930 |
| 17 | 4227083 |
| 18 | 8421504 |
| 19 | 16810113 |
| 20 | 33587330 |
| 21 | 67141763 |
| 22 | 134250632 |
| 23 | 268468361 |
| 24 | 536903818 |
| 25 | 1073774731 |
| 26 | 6442450945 |
| 27 | 10737418242 |
[7,25,42,75,385,642,1155,2184,4233,8330,16523, 98305,163842,294915,557064,1081353,2129930, 4227083,8421504,16810113,33587330,67141763, 134250632,268468361,536903818,1073774731, 6442450945,10737418242] |