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 | 5 |
| 3 | 37 |
| 4 | 361 |
| 5 | 4361 |
| 6 | 62701 |
| 7 | 1044205 |
| 8 | 19748177 |
| 9 | 417787921 |
| 10 | 9770678101 |
| 11 | 250194150581 |
| 12 | 6959638411705 |
| 13 | 208919770666777 |
| 14 | 6729933476435261 |
| 15 | 231512615111396221 |
| 16 | 8469125401589550241 |
| 17 | 328241040596380393505 |
| 18 | 13434223364220816489637 |
| 19 | 578931271898150002093381 |