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 | 5 |
| 2 | 57 |
| 3 | 489 |
| 4 | 4125 |
| 5 | 35117 |
| 6 | 299681 |
| 7 | 2557605 |
| 8 | 21826045 |
| 9 | 186255781 |
| 10 | 1589441093 |
| 11 | 13563736693 |
| 12 | 115748216413 |
| 13 | 987755062201 |
| 14 | 8429158472781 |
| 15 | 71931509371765 |
| 16 | 613838505628281 |
| 17 | 5238284505542721 |
| 18 | 44701699729693429 |
| 19 | 381468772192258129 |
| 20 | 3255321946095461785 |
| 21 | 27779786302899765081 |