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 | 2 |
| 2 | 8 |
| 3 | 34 |
| 4 | 134 |
| 5 | 498 |
| 6 | 1786 |
| 7 | 6274 |
| 8 | 21778 |
| 9 | 75074 |
| 10 | 257762 |
| 11 | 882946 |
| 12 | 3020354 |
| 13 | 10323714 |
| 14 | 35270530 |
| 15 | 120467458 |
| 16 | 411394306 |
| 17 | 1404773378 |
| 18 | 4796567042 |
| 19 | 16377245698 |
| 20 | 55916897282 |
| 21 | 190915194882 |
| 22 | 651831179266 |
| 23 | 2225502715906 |
| 24 | 7598365282306 |
| 25 | 25942489251842 |
| 26 | 88573293551618 |