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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 5 |
| 2 | 12 |
| 3 | 31 |
| 4 | 74 |
| 5 | 184 |
| 6 | 442 |
| 7 | 1081 |
| 8 | 2604 |
| 9 | 6323 |
| 10 | 15250 |
| 11 | 36912 |
| 12 | 89074 |
| 13 | 215293 |
| 14 | 519660 |
| 15 | 1255223 |
| 16 | 3030106 |
| 17 | 7317032 |
| 18 | 17664170 |
| 19 | 42649553 |
| 20 | 102963276 |
| 21 | 248587051 |
| 22 | 600137378 |
| 23 | 1448890464 |
| 24 | 3497918306 |
| 25 | 8444802101 |
| 26 | 20387522508 |
| 27 | 49220043535 |
| 28 | 118827609578 |
| 29 | 286875776920 |
[2,5,12,31,74,184,442,1081,2604,6323,15250,36912, 89074,215293,519660,1255223,3030106,7317032, 17664170,42649553,102963276,248587051,600137378, 1448890464,3497918306,8444802101,20387522508, 49220043535,118827609578,286875776920] |