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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 13 |
| 3 | 11 |
| 4 | 80 |
| 5 | 579 |
| 6 | 2963 |
| 7 | 12224 |
| 8 | 72620 |
| 9 | 426475 |
| 10 | 2284203 |
| 11 | 12768382 |
| 12 | 72904621 |
| 13 | 409673880 |
| 14 | 2298677918 |
| 15 | 13008113489 |
| 16 | 73461302729 |
| 17 | 414141245069 |
| 18 | 2338885431088 |
| 19 | 13210876247129 |
| 20 | 74582366744334 |
| 21 | 421146376787631 |
| 22 | 2378532739728979 |
[0,13,11,80,579,2963,12224,72620,426475,2284203, 12768382,72904621,409673880,2298677918, 13008113489,73461302729,414141245069, 2338885431088,13210876247129,74582366744334, 421146376787631,2378532739728979] |