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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 14 |
| 4 | 28 |
| 5 | 48 |
| 6 | 90 |
| 7 | 200 |
| 8 | 447 |
| 9 | 937 |
| 10 | 1881 |
| 11 | 3813 |
| 12 | 7947 |
| 13 | 16720 |
| 14 | 34862 |
| 15 | 71998 |
| 16 | 148612 |
| 17 | 308152 |
| 18 | 640701 |
| 19 | 1330955 |
| 20 | 2759769 |
| 21 | 5719391 |
| 22 | 11860647 |
| 23 | 24611330 |
| 24 | 51069476 |
| 25 | 105937956 |
| 26 | 219719928 |
| 27 | 455740768 |
| 28 | 945408061 |
| 29 | 1961252075 |
| 30 | 4068435185 |
[1,5,14,28,48,90,200,447,937,1881,3813,7947,16720, 34862,71998,148612,308152,640701,1330955,2759769, 5719391,11860647,24611330,51069476,105937956, 219719928,455740768,945408061,1961252075, 4068435185] |