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) |
|---|---|
| 3 | 7 |
| 4 | 15 |
| 5 | 30 |
| 6 | 74 |
| 7 | 171 |
| 8 | 444 |
| 9 | 1138 |
| 10 | 3048 |
| 11 | 8175 |
| 12 | 22427 |
| 13 | 61686 |
| 14 | 171630 |
| 15 | 479411 |
| 16 | 1347609 |
| 17 | 3801522 |
| 18 | 10768832 |
| 19 | 30595671 |
| 20 | 87190791 |
| 21 | 249085662 |
| 22 | 713268978 |
| 23 | 2046679419 |
| 24 | 5884137206 |
| 25 | 16946037930 |
| 26 | 48882597264 |
| 27 | 141215566135 |
| 28 | 408515830803 |
| 29 | 1183284759846 |
| 30 | 3431523892390 |