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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 24 |
| 4 | 926 |
| 5 | 37282 |
| 6 | 394202 |
| 7 | 2484382 |
| 8 | 10999618 |
| 9 | 38168864 |
| 10 | 110899878 |
| 11 | 281638602 |
| 12 | 643766432 |
| 13 | 1352358921 |
| 14 | 2651129458 |
| 15 | 4906381466 |
| 16 | 8648792662 |
| 17 | 14623854922 |
| 18 | 23851793294 |
| 19 | 37697787702 |
| 20 | 57953320884 |
| 21 | 86929476107 |
| 22 | 127563008202 |
| 23 | 183536011462 |
| 24 | 259410007946 |
| 25 | 360775279732 |
[0,0,24,926,37282,394202,2484382,10999618, 38168864,110899878,281638602,643766432,1352358921, 2651129458,4906381466,8648792662,14623854922, 23851793294,37697787702,57953320884,86929476107, 127563008202,183536011462,259410007946, 360775279732] |