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 | 793 |
| 5 | 3523 |
| 6 | 15469 |
| 7 | 67351 |
| 8 | 291481 |
| 9 | 1255615 |
| 10 | 5388781 |
| 11 | 23057719 |
| 12 | 98412925 |
| 13 | 419147611 |
| 14 | 1781938861 |
| 15 | 7563704443 |
| 16 | 32061034765 |
| 17 | 135735002647 |
| 18 | 574031742241 |
| 19 | 2425263118615 |
| 20 | 10237702739293 |
| 21 | 43181995295227 |
| 22 | 182007967348273 |