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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 5 |
| 5 | 9 |
| 6 | 21 |
| 7 | 93 |
| 8 | 381 |
| 9 | 1551 |
| 10 | 7459 |
| 11 | 56347 |
| 12 | 473995 |
| 13 | 4321181 |
| 14 | 46467441 |
| 15 | 656149111 |
| 16 | 10982021937 |
| 17 | 211884167843 |
| 18 | 4855692779387 |
| 19 | 137589956676037 |
| 20 | 4668303218338689 |
| 21 | 186691871576131219 |
| 22 | 8904751201199219747 |
| 23 | 514295038831216408667 |
[1,1,3,5,9,21,93,381,1551,7459,56347,473995, 4321181,46467441,656149111,10982021937, 211884167843,4855692779387,137589956676037, 4668303218338689,186691871576131219, 8904751201199219747,514295038831216408667] |