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) |
|---|---|
| 4 | 1 |
| 5 | 31 |
| 6 | 337 |
| 7 | 2570 |
| 8 | 16865 |
| 9 | 104858 |
| 10 | 650761 |
| 11 | 4145956 |
| 12 | 27483392 |
| 13 | 190522216 |
| 14 | 1382087111 |
| 15 | 10478149999 |
| 16 | 82860356456 |
| 17 | 682066659044 |
| 18 | 5832719543338 |
| 19 | 51724107920729 |
| 20 | 474869705028520 |
| 21 | 4506715494154371 |
| 22 | 44152005320340946 |