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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 25 |
| 4 | 112 |
| 5 | 414 |
| 6 | 1346 |
| 7 | 3998 |
| 8 | 10966 |
| 9 | 28096 |
| 10 | 67867 |
| 11 | 155632 |
| 12 | 341105 |
| 13 | 717922 |
| 14 | 1456768 |
| 15 | 2859956 |
| 16 | 5449503 |
| 17 | 10102778 |
| 18 | 18266557 |
| 19 | 32275332 |
| 20 | 55823589 |
| 21 | 94667487 |
| 22 | 157629696 |
| 23 | 258017192 |
| 24 | 415654482 |
| 25 | 659686930 |
| 26 | 1032410595 |
| 27 | 1594572418 |
| 28 | 2432482107 |
[1,5,25,112,414,1346,3998,10966,28096,67867, 155632,341105,717922,1456768,2859956,5449503, 10102778,18266557,32275332,55823589,94667487, 157629696,258017192,415654482,659686930, 1032410595,1594572418,2432482107] |