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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 4 |
| 3 | 8 |
| 4 | 17 |
| 5 | 40 |
| 6 | 98 |
| 7 | 247 |
| 8 | 632 |
| 9 | 1632 |
| 10 | 4237 |
| 11 | 11036 |
| 12 | 28802 |
| 13 | 75259 |
| 14 | 196796 |
| 15 | 514840 |
| 16 | 1347257 |
| 17 | 3526176 |
| 18 | 9230050 |
| 19 | 24161999 |
| 20 | 63252752 |
| 21 | 165591088 |
| 22 | 433512149 |
| 23 | 1134931828 |
| 24 | 2971261442 |
| 25 | 7778817075 |
| 26 | 20365132468 |
| 27 | 53316487592 |
| 28 | 139584180257 |
| 29 | 365435810392 |
[3,4,8,17,40,98,247,632,1632,4237,11036,28802, 75259,196796,514840,1347257,3526176,9230050, 24161999,63252752,165591088,433512149,1134931828, 2971261442,7778817075,20365132468,53316487592, 139584180257,365435810392] |