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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 17 |
| 4 | 52 |
| 5 | 137 |
| 6 | 397 |
| 7 | 1082 |
| 8 | 3067 |
| 9 | 8477 |
| 10 | 23812 |
| 11 | 66197 |
| 12 | 185257 |
| 13 | 516242 |
| 14 | 1442527 |
| 15 | 4023737 |
| 16 | 11236372 |
| 17 | 31355057 |
| 18 | 87536917 |
| 19 | 244312202 |
| 20 | 681996787 |
| 21 | 1903557797 |
| 22 | 5313541732 |
| 23 | 14831330717 |
| 24 | 41399039377 |
| 25 | 115555692962 |
| 26 | 322550889847 |
[1,2,7,17,52,137,397,1082,3067,8477,23812,66197, 185257,516242,1442527,4023737,11236372,31355057, 87536917,244312202,681996787,1903557797, 5313541732,14831330717,41399039377,115555692962, 322550889847] |