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 | 2 |
| 2 | 9 |
| 3 | 65 |
| 4 | 719 |
| 5 | 9258 |
| 6 | 133147 |
| 7 | 2477468 |
| 8 | 48452299 |
| 9 | 1000726573 |
| 10 | 21842234124 |
| 11 | 581937143077 |
| 12 | 15852410442671 |
| 13 | 445324580169954 |
| 14 | 12948991063890911 |
| 15 | 390296042740795497 |
| 16 | 13861395944764722457 |
| 17 | 498320813544545374474 |