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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 2 |
| 2 | 10 |
| 3 | 46 |
| 4 | 202 |
| 5 | 862 |
| 6 | 3610 |
| 7 | 14926 |
| 8 | 61162 |
| 9 | 249022 |
| 10 | 1009210 |
| 11 | 4076206 |
| 12 | 16422922 |
| 13 | 66045982 |
| 14 | 265246810 |
| 15 | 1064175886 |
| 16 | 4266269482 |
| 17 | 17093775742 |
| 18 | 68461196410 |
| 19 | 274103065966 |
| 20 | 1097187104842 |
| 21 | 4391072942302 |
| 22 | 17571265338010 |
| 23 | 70305982058446 |
| 24 | 281286690353002 |
| 25 | 1125335047769662 |
[0,2,10,46,202,862,3610,14926,61162,249022, 1009210,4076206,16422922,66045982,265246810, 1064175886,4266269482,17093775742,68461196410, 274103065966,1097187104842,4391072942302, 17571265338010,70305982058446,281286690353002, 1125335047769662] |