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 | 3 |
| 3 | 6 |
| 4 | 11 |
| 5 | 26 |
| 6 | 68 |
| 7 | 177 |
| 8 | 492 |
| 9 | 1403 |
| 10 | 4113 |
| 11 | 12149 |
| 12 | 36225 |
| 13 | 108268 |
| 14 | 324529 |
| 15 | 973163 |
| 16 | 2920533 |
| 17 | 8764041 |
| 18 | 26303715 |
| 19 | 78935398 |
| 20 | 236878491 |
| 21 | 710783343 |