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 | 41 |
| 3 | 227 |
| 4 | 1221 |
| 5 | 6447 |
| 6 | 33601 |
| 7 | 173467 |
| 8 | 889181 |
| 9 | 4533287 |
| 10 | 23015961 |
| 11 | 116477907 |
| 12 | 587981941 |
| 13 | 2962279327 |
| 14 | 14900875121 |
| 15 | 74862289547 |
| 16 | 375743103501 |
| 17 | 1884442140567 |
| 18 | 9445117195081 |
| 19 | 47317211944387 |
| 20 | 236952563597861 |