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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 6 |
| 3 | 12 |
| 4 | 25 |
| 5 | 53 |
| 6 | 116 |
| 7 | 259 |
| 8 | 593 |
| 9 | 1382 |
| 10 | 3281 |
| 11 | 7897 |
| 12 | 19252 |
| 13 | 47391 |
| 14 | 117645 |
| 15 | 293934 |
| 16 | 738341 |
| 17 | 1862341 |
| 18 | 4713220 |
| 19 | 11959211 |
| 20 | 30407929 |
| 21 | 77440630 |
| 22 | 197470825 |
| 23 | 504041249 |
| 24 | 1287558068 |
| 25 | 3291018759 |
| 26 | 8415888789 |
| 27 | 21529314366 |
| 28 | 55091691997 |
| 29 | 141006790829 |
[3,6,12,25,53,116,259,593,1382,3281,7897,19252, 47391,117645,293934,738341,1862341,4713220, 11959211,30407929,77440630,197470825,504041249, 1287558068,3291018759,8415888789,21529314366, 55091691997,141006790829] |