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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 19 |
| 3 | 61 |
| 4 | 146 |
| 5 | 336 |
| 6 | 757 |
| 7 | 1711 |
| 8 | 3868 |
| 9 | 8752 |
| 10 | 19680 |
| 11 | 43869 |
| 12 | 96695 |
| 13 | 210638 |
| 14 | 453863 |
| 15 | 968875 |
| 16 | 2053227 |
| 17 | 4328457 |
| 18 | 9093933 |
| 19 | 19068574 |
| 20 | 39943650 |
| 21 | 83628355 |
| 22 | 175018478 |
| 23 | 366081158 |
| 24 | 765102861 |
| 25 | 1597315609 |
| 26 | 3330380539 |
| 27 | 6933810090 |
| 28 | 14414812994 |
| 29 | 29924339675 |
| 30 | 62038821363 |
[1,5,19,61,146,336,757,1711,3868,8752,19680,43869, 96695,210638,453863,968875,2053227,4328457, 9093933,19068574,39943650,83628355,175018478, 366081158,765102861,1597315609,3330380539, 6933810090,14414812994,29924339675,62038821363] |