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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 47 |
| 4 | 205 |
| 5 | 915 |
| 6 | 4197 |
| 7 | 19445 |
| 8 | 90887 |
| 9 | 429091 |
| 10 | 2036615 |
| 11 | 9711097 |
| 12 | 46538103 |
| 13 | 223736955 |
| 14 | 1078659981 |
| 15 | 5215774821 |
| 16 | 25273555029 |
| 17 | 122695169497 |
| 18 | 596801074495 |
| 19 | 2907185919885 |
| 20 | 14180614357021 |
| 21 | 69263754392477 |
| 22 | 338679866816603 |
| 23 | 1657693556708723 |
| 24 | 8121805455346329 |
| 25 | 39825586824526497 |
| 26 | 195436160696250531 |
[1,3,11,47,205,915,4197,19445,90887,429091, 2036615,9711097,46538103,223736955,1078659981, 5215774821,25273555029,122695169497,596801074495, 2907185919885,14180614357021,69263754392477, 338679866816603,1657693556708723,8121805455346329, 39825586824526497,195436160696250531] |