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 | 2 |
| 4 | 8 |
| 5 | 31 |
| 6 | 97 |
| 7 | 264 |
| 8 | 654 |
| 9 | 1518 |
| 10 | 3366 |
| 11 | 7227 |
| 12 | 15169 |
| 13 | 31339 |
| 14 | 64043 |
| 15 | 129906 |
| 16 | 262192 |
| 17 | 527444 |
| 18 | 1058764 |
| 19 | 2122373 |
| 20 | 4250731 |
| 21 | 8508777 |
| 22 | 17026409 |
| 23 | 34063444 |
| 24 | 68139538 |
| 25 | 136294026 |
| 26 | 272605602 |
| 27 | 545231679 |
| 28 | 1090487109 |
| 29 | 2181001623 |