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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 75 |
| 5 | 289 |
| 6 | 1329 |
| 7 | 5635 |
| 8 | 26397 |
| 9 | 116593 |
| 10 | 552593 |
| 11 | 2506239 |
| 12 | 11979623 |
| 13 | 55316481 |
| 14 | 266066767 |
| 15 | 1244457787 |
| 16 | 6014193317 |
| 17 | 28401812231 |
| 18 | 137771141551 |
| 19 | 655491800229 |
| 20 | 3189195262765 |
| 21 | 15263886550913 |
| 22 | 74447327834795 |
| 23 | 358032324714527 |
| 24 | 1749853945686871 |
| 25 | 8448874986136843 |
| 26 | 41365559604166123 |
| 27 | 200391378903857941 |
[1,1,5,17,75,289,1329,5635,26397,116593,552593, 2506239,11979623,55316481,266066767,1244457787, 6014193317,28401812231,137771141551,655491800229, 3189195262765,15263886550913,74447327834795, 358032324714527,1749853945686871,8448874986136843, 41365559604166123,200391378903857941] |