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 | 1 |
| 1 | 4 |
| 2 | 17 |
| 3 | 82 |
| 4 | 457 |
| 5 | 2936 |
| 6 | 21529 |
| 7 | 178102 |
| 8 | 1644017 |
| 9 | 16768972 |
| 10 | 187417921 |
| 11 | 2278607354 |
| 12 | 29947410937 |
| 13 | 423169937152 |
| 14 | 6398329449737 |
| 15 | 103084196690206 |
| 16 | 1763095226149729 |
| 17 | 31906336189354772 |
| 18 | 609120963614954737 |