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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 64 |
| 3 | 168 |
| 4 | 558 |
| 5 | 1586 |
| 6 | 3726 |
| 7 | 9450 |
| 8 | 21318 |
| 9 | 47518 |
| 10 | 104470 |
| 11 | 220531 |
| 12 | 464202 |
| 13 | 957412 |
| 14 | 1949906 |
| 15 | 3940218 |
| 16 | 7868976 |
| 17 | 15610980 |
| 18 | 30742563 |
| 19 | 60142488 |
| 20 | 117047084 |
| 21 | 226575095 |
| 22 | 436635184 |
| 23 | 837955970 |
| 24 | 1601924662 |
| 25 | 3051891570 |
| 26 | 5795441060 |
| 27 | 10972726928 |
[8,64,168,558,1586,3726,9450,21318,47518,104470, 220531,464202,957412,1949906,3940218,7868976, 15610980,30742563,60142488,117047084,226575095, 436635184,837955970,1601924662,3051891570, 5795441060,10972726928] |