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| n | a(n) |
|---|---|
| 4 | 25 |
| 5 | 454 |
| 6 | 3818 |
| 7 | 21420 |
| 8 | 92805 |
| 9 | 335152 |
| 10 | 1055944 |
| 11 | 2990020 |
| 12 | 7767357 |
| 13 | 18789070 |
| 14 | 42797602 |
| 15 | 92588216 |
| 16 | 191542842 |
| 17 | 381000192 |
| 18 | 731941256 |
| 19 | 1363109096 |
| 20 | 2468549141 |
| 21 | 4358716470 |
| 22 | 7520830306 |
| 23 | 12706161124 |
| 24 | 21054530855 |
| 25 | 34269633840 |
| 26 | 54863015040 |
| 27 | 86489873580 |
| 28 | 134406530985 |
[25,454,3818,21420,92805,335152,1055944,2990020, 7767357,18789070,42797602,92588216,191542842, 381000192,731941256,1363109096,2468549141, 4358716470,7520830306,12706161124,21054530855, 34269633840,54863015040,86489873580,134406530985] |