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) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 77 |
| 4 | 1519 |
| 5 | 12987 |
| 6 | 111035 |
| 7 | 2190397 |
| 8 | 18727245 |
| 9 | 160112393 |
| 10 | 3158550955 |
| 11 | 27004674303 |
| 12 | 230881959671 |
| 13 | 4554628286713 |
| 14 | 38940721617681 |
| 15 | 332931625733189 |
| 16 | 6567770830889191 |
| 17 | 56152493568021699 |
| 18 | 480087173425298867 |
| 19 | 9470720983513926709 |
| 20 | 80971856784365672277 |