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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 25 |
| 2 | 73 |
| 3 | 215 |
| 4 | 635 |
| 5 | 1879 |
| 6 | 5567 |
| 7 | 16509 |
| 8 | 48993 |
| 9 | 145479 |
| 10 | 432191 |
| 11 | 1284481 |
| 12 | 3818837 |
| 13 | 11357069 |
| 14 | 33784477 |
| 15 | 100524263 |
| 16 | 299168955 |
| 17 | 890522631 |
| 18 | 2651236335 |
| 19 | 7894421265 |
| 20 | 23510114133 |
| 21 | 70023966177 |
| 22 | 208589168433 |
| 23 | 621421019043 |
| 24 | 1851508693479 |
[1,25,73,215,635,1879,5567,16509,48993,145479, 432191,1284481,3818837,11357069,33784477, 100524263,299168955,890522631,2651236335, 7894421265,23510114133,70023966177,208589168433, 621421019043,1851508693479] |