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 | 9 |
| 5 | 29 |
| 6 | 105 |
| 7 | 431 |
| 8 | 1969 |
| 9 | 9785 |
| 10 | 52145 |
| 11 | 296155 |
| 12 | 1787385 |
| 13 | 11428949 |
| 14 | 77124569 |
| 15 | 546987143 |
| 16 | 4062341601 |
| 17 | 31502219889 |
| 18 | 254500383457 |
| 19 | 2137863653811 |
| 20 | 18639586581097 |
| 21 | 168387382189709 |
| 22 | 1573599537048265 |
| 23 | 15189509662516063 |
| 24 | 151243491212611217 |
| 25 | 1551565158004180137 |