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) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 47 |
| 4 | 319 |
| 5 | 1879 |
| 6 | 20417 |
| 7 | 263111 |
| 8 | 52279 |
| 9 | 1768477 |
| 10 | 33464927 |
| 11 | 166770367 |
| 12 | 3825136961 |
| 13 | 19081066231 |
| 14 | 57128792093 |
| 15 | 236266661971 |
| 16 | 7313175618421 |
| 17 | 14606816124167 |
| 18 | 102126365345729 |
| 19 | 3774664307989373 |
| 20 | 3771059091081773 |