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 | 3 |
| 1 | 19 |
| 2 | 149 |
| 3 | 1249 |
| 4 | 10673 |
| 5 | 91849 |
| 6 | 793649 |
| 7 | 6880249 |
| 8 | 59824193 |
| 9 | 521638729 |
| 10 | 4560527249 |
| 11 | 39970996249 |
| 12 | 351149017313 |
| 13 | 3091621650409 |
| 14 | 27274838982449 |
| 15 | 241075504216249 |
| 16 | 2134495165628033 |
| 17 | 18928981513482889 |
| 18 | 168109033806743249 |