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 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 4 |
| 7 | 7 |
| 8 | 22 |
| 9 | 60 |
| 10 | 208 |
| 11 | 695 |
| 12 | 2566 |
| 13 | 9451 |
| 14 | 36158 |
| 15 | 139574 |
| 16 | 548347 |
| 17 | 2174801 |
| 18 | 8719651 |
| 19 | 35244472 |
| 20 | 143581782 |
| 21 | 588858667 |
| 22 | 2430036786 |
| 23 | 10083626092 |
| 24 | 42055927173 |
| 25 | 176217259551 |
| 26 | 741517642476 |
| 27 | 3132564196880 |
| 28 | 13281805256068 |
| 29 | 56503895845238 |
| 30 | 241135999611542 |