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 | 3 |
| 1 | 10 |
| 2 | 63 |
| 3 | 199 |
| 4 | 1257 |
| 5 | 3970 |
| 6 | 25077 |
| 7 | 79201 |
| 8 | 500283 |
| 9 | 1580050 |
| 10 | 9980583 |
| 11 | 31521799 |
| 12 | 199111377 |
| 13 | 628855930 |
| 14 | 3972246957 |
| 15 | 12545596801 |
| 16 | 79245827763 |
| 17 | 250283080090 |
| 18 | 1580944308303 |
| 19 | 4993116004999 |
| 20 | 31539640338297 |