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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 10 |
| 4 | 20 |
| 5 | 41 |
| 6 | 86 |
| 7 | 192 |
| 8 | 441 |
| 9 | 1039 |
| 10 | 2493 |
| 11 | 6072 |
| 12 | 14960 |
| 13 | 37199 |
| 14 | 93193 |
| 15 | 234957 |
| 16 | 595562 |
| 17 | 1516639 |
| 18 | 3877905 |
| 19 | 9950908 |
| 20 | 25615654 |
| 21 | 66127187 |
| 22 | 171144672 |
| 23 | 443966371 |
| 24 | 1154115393 |
| 25 | 3005950908 |
[1,5,10,20,41,86,192,441,1039,2493,6072,14960, 37199,93193,234957,595562,1516639,3877905,9950908, 25615654,66127187,171144672,443966371,1154115393, 3005950908] |