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 | 3 |
| 2 | 6 |
| 3 | 13 |
| 4 | 36 |
| 5 | 138 |
| 6 | 736 |
| 7 | 4908 |
| 8 | 36351 |
| 9 | 280228 |
| 10 | 2190651 |
| 11 | 17206203 |
| 12 | 135357481 |
| 13 | 1065387963 |
| 14 | 8387050686 |
| 15 | 66029196613 |
| 16 | 519841755036 |
| 17 | 4092692363058 |
| 18 | 32221664474776 |
| 19 | 253680537891828 |
| 20 | 1997222414704551 |
| 21 | 15724098193422028 |
| 22 | 123795561597659331 |
| 23 | 974640390569138163 |