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) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 12 |
| 5 | 53 |
| 6 | 234 |
| 7 | 1013 |
| 8 | 4306 |
| 9 | 18051 |
| 10 | 74903 |
| 11 | 308487 |
| 12 | 1263393 |
| 13 | 5152139 |
| 14 | 20941298 |
| 15 | 84897207 |
| 16 | 343467388 |
| 17 | 1387244237 |
| 18 | 5595368133 |
| 19 | 22543241377 |
| 20 | 90739796783 |
| 21 | 364954106877 |
| 22 | 1466865660103 |
| 23 | 5892463315373 |
| 24 | 23658818086719 |
| 25 | 94952826295865 |
| 26 | 380947979933041 |
| 27 | 1527871081396065 |
| 28 | 6126157580638517 |
| 29 | 24557525359295337 |
| 30 | 98421154766829972 |