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) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 11 |
| 5 | 34 |
| 6 | 107 |
| 7 | 312 |
| 8 | 882 |
| 9 | 2457 |
| 10 | 6504 |
| 11 | 17206 |
| 12 | 46073 |
| 13 | 123868 |
| 14 | 334567 |
| 15 | 915443 |
| 16 | 2520503 |
| 17 | 7002043 |
| 18 | 19604493 |
| 19 | 55264235 |