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 | 4 |
| 2 | 17 |
| 3 | 78 |
| 4 | 393 |
| 5 | 2208 |
| 6 | 13977 |
| 7 | 100026 |
| 8 | 806769 |
| 9 | 7280604 |
| 10 | 72865089 |
| 11 | 801693126 |
| 12 | 9620848953 |
| 13 | 125072630712 |
| 14 | 1751021612937 |
| 15 | 26265338542962 |
| 16 | 420245459734113 |
| 17 | 7144172944620084 |
| 18 | 128595113390582001 |
| 19 | 2443307155583319486 |
| 20 | 48866143115153174121 |