This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 21 |
| 2 | 441 |
| 3 | 9261 |
| 4 | 194481 |
| 5 | 4084101 |
| 6 | 85766121 |
| 7 | 1801088541 |
| 8 | 37822859361 |
| 9 | 794280046581 |
| 10 | 16679880978201 |
| 11 | 350277500542221 |
| 12 | 7355827511386641 |
| 13 | 154472377739119461 |
| 14 | 3243919932521508681 |
| 15 | 68122318582951682301 |
| 16 | 1430568690241985328321 |
| 17 | 30041942495081691894741 |
| 18 | 630880792396715529789561 |
| 19 | 13248496640331026125580781 |
| 20 | 278218429446951548637196401 |