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 | 3 |
| 4 | 18 |
| 5 | 33 |
| 6 | 111 |
| 7 | 690 |
| 8 | 1269 |
| 9 | 4292 |
| 10 | 26705 |
| 11 | 49118 |
| 12 | 166165 |
| 13 | 1033922 |
| 14 | 1901679 |
| 15 | 6433333 |
| 16 | 40029886 |
| 17 | 73626439 |
| 18 | 249076459 |
| 19 | 1549819116 |
| 20 | 2850561773 |
| 21 | 9643381402 |
| 22 | 60003650693 |
| 23 | 110363919984 |
| 24 | 373358466957 |
| 25 | 2323134396636 |
| 26 | 4272910326315 |