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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 511 |
| 3 | 19684 |
| 4 | 261631 |
| 5 | 1953126 |
| 6 | 10058524 |
| 7 | 40353608 |
| 8 | 133955071 |
| 9 | 387440173 |
| 10 | 998047386 |
| 11 | 2357947692 |
| 12 | 5149944604 |
| 13 | 10604499374 |
| 14 | 20620693688 |
| 15 | 38445332184 |
| 16 | 68584996351 |
| 17 | 118587876498 |
| 18 | 197981928403 |
| 19 | 322687697780 |
| 20 | 510998308506 |
| 21 | 794320419872 |
| 22 | 1204911270612 |
| 23 | 1801152661464 |
| 24 | 2636771617564 |
| 25 | 3814699218751 |
[1,511,19684,261631,1953126,10058524,40353608, 133955071,387440173,998047386,2357947692, 5149944604,10604499374,20620693688,38445332184, 68584996351,118587876498,197981928403, 322687697780,510998308506,794320419872, 1204911270612,1801152661464,2636771617564, 3814699218751] |