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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 13 |
| 4 | 59 |
| 5 | 197 |
| 6 | 921 |
| 7 | 3331 |
| 8 | 15865 |
| 9 | 60727 |
| 10 | 290267 |
| 11 | 1154275 |
| 12 | 5560547 |
| 13 | 22622223 |
| 14 | 109636859 |
| 15 | 454582257 |
| 16 | 2209362255 |
| 17 | 9300526153 |
| 18 | 45349547541 |
| 19 | 193067942897 |
| 20 | 943931822673 |
| 21 | 4058053450409 |
| 22 | 19874749597221 |
| 23 | 86155750783929 |
| 24 | 422686506792649 |
| 25 | 1844846909082093 |
| 26 | 9064441951114577 |
| 27 | 39801583197772329 |
[1,1,5,13,59,197,921,3331,15865,60727,290267, 1154275,5560547,22622223,109636859,454582257, 2209362255,9300526153,45349547541,193067942897, 943931822673,4058053450409,19874749597221, 86155750783929,422686506792649,1844846909082093, 9064441951114577,39801583197772329] |