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 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 17 |
| 5 | 176 |
| 6 | 2287 |
| 7 | 49540 |
| 8 | 1518337 |
| 9 | 67457584 |
| 10 | 4254836111 |
| 11 | 376795261844 |
| 12 | 46709151254449 |
| 13 | 8061849904932136 |
| 14 | 1936383997541071639 |
| 15 | 646603398091877815516 |
| 16 | 300476951799493029958913 |