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 | 1 |
| 2 | 7 |
| 3 | 47 |
| 4 | 497 |
| 5 | 6241 |
| 6 | 95767 |
| 7 | 1704527 |
| 8 | 34741217 |
| 9 | 796079041 |
| 10 | 20273087527 |
| 11 | 567864586607 |
| 12 | 17352768515537 |
| 13 | 574448847467041 |
| 14 | 20479521468959287 |
| 15 | 782259922208550287 |
| 16 | 31872138933891307457 |
| 17 | 1379749466246228538241 |
| 18 | 63243057486503656319047 |
| 19 | 3059895336952604166395567 |