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 | 2 |
| 5 | 3 |
| 6 | 7 |
| 7 | 13 |
| 8 | 33 |
| 9 | 73 |
| 10 | 202 |
| 11 | 488 |
| 12 | 1441 |
| 13 | 3741 |
| 14 | 11496 |
| 15 | 31311 |
| 16 | 98607 |
| 17 | 278840 |
| 18 | 895137 |
| 19 | 2599071 |
| 20 | 8452620 |