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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 80 |
| 3 | 428 |
| 4 | 1428 |
| 5 | 3604 |
| 6 | 7924 |
| 7 | 14988 |
| 8 | 26244 |
| 9 | 43072 |
| 10 | 66844 |
| 11 | 98804 |
| 12 | 142652 |
| 13 | 197584 |
| 14 | 268800 |
| 15 | 357608 |
| 16 | 465888 |
| 17 | 596964 |
| 18 | 756036 |
| 19 | 942160 |
| 20 | 1163608 |
| 21 | 1420248 |
| 22 | 1717344 |
| 23 | 2056952 |
| 24 | 2451248 |
| 25 | 2891420 |
| 26 | 3392528 |
| 27 | 3958576 |
[4,80,428,1428,3604,7924,14988,26244,43072,66844, 98804,142652,197584,268800,357608,465888,596964, 756036,942160,1163608,1420248,1717344,2056952, 2451248,2891420,3392528,3958576] |