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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 9 |
| 6 | 25 |
| 7 | 71 |
| 8 | 219 |
| 9 | 689 |
| 10 | 2189 |
| 11 | 7059 |
| 12 | 23091 |
| 13 | 76331 |
| 14 | 254489 |
| 15 | 855057 |
| 16 | 2892611 |
| 17 | 9843695 |
| 18 | 33674049 |
| 19 | 115735093 |
| 20 | 399448699 |
| 21 | 1383893277 |
| 22 | 4811005765 |
| 23 | 16777546935 |
| 24 | 58676543307 |
| 25 | 205751099671 |
| 26 | 723221934973 |
| 27 | 2547846317025 |
| 28 | 8994482626499 |
| 29 | 31813908928389 |
| 30 | 112729816817649 |
| 31 | 400119890812663 |
| 32 | 1422409369378787 |
| 33 | 5064073900824483 |
| 34 | 18054192195882181 |
| 35 | 64450109043795285 |
| 36 | 230358773955266667 |
[1,1,1,3,9,25,71,219,689,2189,7059,23091,76331, 254489,855057,2892611,9843695,33674049,115735093, 399448699,1383893277,4811005765,16777546935, 58676543307,205751099671,723221934973, 2547846317025,8994482626499,31813908928389, 112729816817649,400119890812663,1422409369378787, 5064073900824483,18054192195882181, 64450109043795285,230358773955266667] |