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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 5 |
| 3 | 17 |
| 4 | 61 |
| 5 | 166 |
| 6 | 421 |
| 7 | 981 |
| 8 | 2177 |
| 9 | 4634 |
| 10 | 9564 |
| 11 | 19244 |
| 12 | 37934 |
| 13 | 73502 |
| 14 | 140373 |
| 15 | 264783 |
| 16 | 494143 |
| 17 | 913618 |
| 18 | 1675387 |
| 19 | 3050075 |
| 20 | 5516865 |
| 21 | 9920880 |
| 22 | 17747270 |
| 23 | 31597272 |
| 24 | 56013036 |
| 25 | 98903436 |
| 26 | 174003461 |
| 27 | 305107901 |
| 28 | 533345617 |
| 29 | 929655934 |
| 30 | 1616151649 |
[0,5,17,61,166,421,981,2177,4634,9564,19244,37934, 73502,140373,264783,494143,913618,1675387,3050075, 5516865,9920880,17747270,31597272,56013036, 98903436,174003461,305107901,533345617,929655934, 1616151649] |