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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 10 |
| 4 | 20 |
| 5 | 41 |
| 6 | 100 |
| 7 | 205 |
| 8 | 500 |
| 9 | 1025 |
| 10 | 2500 |
| 11 | 5125 |
| 12 | 11753 |
| 13 | 25625 |
| 14 | 58765 |
| 15 | 128125 |
| 16 | 293825 |
| 17 | 640625 |
| 18 | 1469125 |
| 19 | 3203125 |
| 20 | 7345625 |
| 21 | 16015625 |
| 22 | 34867797 |
| 23 | 80078125 |
| 24 | 174338985 |
| 25 | 400390625 |
| 26 | 871694925 |
| 27 | 2001953125 |
| 28 | 4358474625 |
| 29 | 10009765625 |
| 30 | 21792373125 |
| 31 | 50048828125 |
[1,2,4,10,20,41,100,205,500,1025,2500,5125,11753, 25625,58765,128125,293825,640625,1469125,3203125, 7345625,16015625,34867797,80078125,174338985, 400390625,871694925,2001953125,4358474625, 10009765625,21792373125,50048828125] |