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 | 2 |
| 3 | 6 |
| 4 | 51 |
| 5 | 114 |
| 6 | 136 |
| 7 | 149 |
| 8 | 1388 |
| 9 | 3654 |
| 10 | 3961 |
| 11 | 41614 |
| 12 | 2975365 |
| 13 | 4120126 |
| 14 | 5760908 |
| 15 | 11210809 |
| 16 | 21235067 |
| 17 | 43239302 |
| 18 | 156258546 |
| 19 | 230627452 |
| 20 | 595763433 |
| 21 | 4709180601 |
| 22 | 148918280487 |
| 23 | 841708059551 |
| 24 | 2895551449652 |
| 25 | 5660433533409 |
| 26 | 6575950336213 |