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 | 29 |
| 3 | 145 |
| 4 | 523 |
| 5 | 2717 |
| 6 | 14462 |
| 7 | 68919 |
| 8 | 332306 |
| 9 | 1652441 |
| 10 | 8140067 |
| 11 | 39816114 |
| 12 | 195543171 |
| 13 | 961617387 |
| 14 | 4722204339 |
| 15 | 23186542778 |
| 16 | 113898106759 |
| 17 | 559470061363 |
| 18 | 2747805117373 |
| 19 | 13496167444555 |
| 20 | 66289849507630 |
| 21 | 325594360281088 |