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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 16 |
| 3 | 64 |
| 4 | 256 |
| 5 | 1025 |
| 6 | 4095 |
| 7 | 16395 |
| 8 | 65545 |
| 9 | 262250 |
| 10 | 1048875 |
| 11 | 4195700 |
| 12 | 16782525 |
| 13 | 67130375 |
| 14 | 268521500 |
| 15 | 1074085000 |
| 16 | 4296343625 |
| 17 | 17185365000 |
| 18 | 68741481250 |
| 19 | 274965882500 |
| 20 | 1099863606875 |
| 21 | 4399454303125 |
| 22 | 17597817384375 |
| 23 | 70391269365625 |
[1,4,16,64,256,1025,4095,16395,65545,262250, 1048875,4195700,16782525,67130375,268521500, 1074085000,4296343625,17185365000,68741481250, 274965882500,1099863606875,4399454303125, 17597817384375,70391269365625] |