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 | 13 |
| 3 | 41 |
| 4 | 281 |
| 5 | 1183 |
| 6 | 6728 |
| 7 | 31529 |
| 8 | 167089 |
| 9 | 817991 |
| 10 | 4213133 |
| 11 | 21001799 |
| 12 | 106912793 |
| 13 | 536948224 |
| 14 | 2720246633 |
| 15 | 13704300553 |
| 16 | 69289288909 |
| 17 | 349519610713 |
| 18 | 1765722581057 |
| 19 | 8911652846951 |
| 20 | 45005025662792 |
| 21 | 227191499132401 |
| 22 | 1147185247901449 |
| 23 | 5791672851807479 |