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 | 2 |
| 2 | 22 |
| 3 | 170 |
| 4 | 1366 |
| 5 | 10922 |
| 6 | 87382 |
| 7 | 699050 |
| 8 | 5592406 |
| 9 | 44739242 |
| 10 | 357913942 |
| 11 | 2863311530 |
| 12 | 22906492246 |
| 13 | 183251937962 |
| 14 | 1466015503702 |
| 15 | 11728124029610 |
| 16 | 93824992236886 |
| 17 | 750599937895082 |
| 18 | 6004799503160662 |
| 19 | 48038396025285290 |
| 20 | 384307168202282326 |
| 21 | 3074457345618258602 |