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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 0 |
| 4 | 5 |
| 5 | 5 |
| 6 | 0 |
| 7 | 25 |
| 8 | 25 |
| 9 | 0 |
| 10 | 125 |
| 11 | 125 |
| 12 | 0 |
| 13 | 625 |
| 14 | 625 |
| 15 | 0 |
| 16 | 3125 |
| 17 | 3125 |
| 18 | 0 |
| 19 | 15625 |
| 20 | 15625 |
| 21 | 0 |
| 22 | 78125 |
| 23 | 78125 |
| 24 | 0 |
| 25 | 390625 |
| 26 | 390625 |
| 27 | 0 |
| 28 | 1953125 |
| 29 | 1953125 |
| 30 | 0 |
| 31 | 9765625 |
| 32 | 9765625 |
| 33 | 0 |
| 34 | 48828125 |
| 35 | 48828125 |
| 36 | 0 |
| 37 | 244140625 |
| 38 | 244140625 |
| 39 | 0 |
| 40 | 1220703125 |
| 41 | 1220703125 |
| 42 | 0 |
[0,1,1,0,5,5,0,25,25,0,125,125,0,625,625,0,3125, 3125,0,15625,15625,0,78125,78125,0,390625,390625, 0,1953125,1953125,0,9765625,9765625,0,48828125, 48828125,0,244140625,244140625,0,1220703125, 1220703125,0] |