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 | 7 |
| 2 | 37 |
| 3 | 175 |
| 4 | 925 |
| 5 | 4977 |
| 6 | 27067 |
| 7 | 147777 |
| 8 | 808165 |
| 9 | 4422703 |
| 10 | 24210127 |
| 11 | 132542813 |
| 12 | 725664307 |
| 13 | 3973047319 |
| 14 | 21752799623 |
| 15 | 119098967235 |
| 16 | 652080798837 |
| 17 | 3570220727531 |
| 18 | 19547391880633 |
| 19 | 107024353337437 |
| 20 | 585971402810715 |