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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 25 |
| 4 | 93 |
| 5 | 353 |
| 6 | 1358 |
| 7 | 5273 |
| 8 | 20614 |
| 9 | 81003 |
| 10 | 319584 |
| 11 | 1264924 |
| 12 | 5019743 |
| 13 | 19963699 |
| 14 | 79541181 |
| 15 | 317406302 |
| 16 | 1268283199 |
| 17 | 5073605801 |
| 18 | 20316709251 |
| 19 | 81427911966 |
| 20 | 326612013623 |
| 21 | 1310968893954 |
| 22 | 5265285993860 |
| 23 | 21158914176719 |
| 24 | 85071253608611 |
[1,2,7,25,93,353,1358,5273,20614,81003,319584, 1264924,5019743,19963699,79541181,317406302, 1268283199,5073605801,20316709251,81427911966, 326612013623,1310968893954,5265285993860, 21158914176719,85071253608611] |