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 | 7 |
| 2 | 49 |
| 3 | 5215 |
| 4 | 21841937 |
| 5 | 3430832678207 |
| 6 | 21070560836988719941 |
| 7 | 5258020825380244651432771257 |
| 8 | 54855616345977485934984671841940089233 |