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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 272 |
| 3 | 3272 |
| 4 | 18652 |
| 5 | 71630 |
| 6 | 214724 |
| 7 | 542850 |
| 8 | 1211784 |
| 9 | 2459988 |
| 10 | 4633800 |
| 11 | 8215988 |
| 12 | 13857668 |
| 13 | 22413586 |
| 14 | 34980764 |
| 15 | 52940510 |
| 16 | 78003792 |
| 17 | 112259976 |
| 18 | 158228928 |
| 19 | 218916480 |
| 20 | 297873260 |
| 21 | 399256886 |
| 22 | 527897524 |
| 23 | 689366810 |
| 24 | 890050136 |
| 25 | 1137222300 |
[0,272,3272,18652,71630,214724,542850,1211784, 2459988,4633800,8215988,13857668,22413586, 34980764,52940510,78003792,112259976,158228928, 218916480,297873260,399256886,527897524,689366810, 890050136,1137222300] |