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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 11 |
| 3 | 55 |
| 4 | 275 |
| 5 | 1375 |
| 6 | 6875 |
| 7 | 34375 |
| 8 | 171875 |
| 9 | 859375 |
| 10 | 4296875 |
| 11 | 21484375 |
| 12 | 107421875 |
| 13 | 537109375 |
| 14 | 2685546875 |
| 15 | 13427734375 |
| 16 | 67138671875 |
| 17 | 335693359375 |
| 18 | 1678466796875 |
| 19 | 8392333984375 |
| 20 | 41961669921875 |
| 21 | 209808349609375 |
[1,5,11,55,275,1375,6875,34375,171875,859375, 4296875,21484375,107421875,537109375,2685546875, 13427734375,67138671875,335693359375, 1678466796875,8392333984375,41961669921875, 209808349609375] |