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) |
|---|---|
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 6 |
| 6 | 12 |
| 7 | 26 |
| 8 | 59 |
| 9 | 146 |
| 10 | 368 |
| 11 | 976 |
| 12 | 2667 |
| 13 | 7482 |
| 14 | 21440 |
| 15 | 62622 |
| 16 | 185637 |
| 17 | 557680 |
| 18 | 1694256 |
| 19 | 5198142 |
| 20 | 16086486 |
| 21 | 50165218 |
| 22 | 157510504 |
| 23 | 497607008 |
| 24 | 1580800091 |
| 25 | 5047337994 |
| 26 | 16190223624 |
| 27 | 52153429218 |
| 28 | 168657986843 |
| 29 | 547389492416 |