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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 7 |
| 3 | 10 |
| 4 | 21 |
| 5 | 44 |
| 6 | 83 |
| 7 | 168 |
| 8 | 365 |
| 9 | 766 |
| 10 | 1615 |
| 11 | 3490 |
| 12 | 7555 |
| 13 | 16450 |
| 14 | 36279 |
| 15 | 80602 |
| 16 | 180187 |
| 17 | 405906 |
| 18 | 920301 |
| 19 | 2097902 |
| 20 | 4807235 |
| 21 | 11066060 |
| 22 | 25572903 |
| 23 | 59300268 |
| 24 | 137919877 |
| 25 | 321585732 |
| 26 | 751461855 |
| 27 | 1759215072 |
| 28 | 4124852047 |
| 29 | 9684327044 |
| 30 | 22762103611 |
[3,7,10,21,44,83,168,365,766,1615,3490,7555,16450, 36279,80602,180187,405906,920301,2097902,4807235, 11066060,25572903,59300268,137919877,321585732, 751461855,1759215072,4124852047,9684327044, 22762103611] |