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) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 47 |
| 4 | 406 |
| 5 | 5320 |
| 6 | 65209 |
| 7 | 876865 |
| 8 | 12428079 |
| 9 | 187013213 |
| 10 | 2977639454 |
| 11 | 50100075551 |
| 12 | 889030153223 |
| 13 | 16605705694513 |
| 14 | 325842147818131 |
| 15 | 6704025812865230 |
| 16 | 144359437306938642 |
| 17 | 3247712172059705741 |
| 18 | 76210676599647821811 |
| 19 | 1862449116865631232577 |