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 | 4 |
| 4 | 10 |
| 5 | 24 |
| 6 | 66 |
| 7 | 176 |
| 8 | 493 |
| 9 | 1362 |
| 10 | 3821 |
| 11 | 10660 |
| 12 | 29864 |
| 13 | 83329 |
| 14 | 232702 |
| 15 | 648182 |
| 16 | 1804901 |
| 17 | 5015725 |
| 18 | 13931755 |
| 19 | 38635673 |
| 20 | 107090666 |
| 21 | 296449133 |
| 22 | 820271143 |
| 23 | 2267225157 |
| 24 | 6264244414 |
| 25 | 17291930470 |