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 | 2 |
| 3 | 4 |
| 4 | 5 |
| 5 | 7 |
| 6 | 19 |
| 7 | 39 |
| 8 | 121 |
| 9 | 321 |
| 10 | 813 |
| 11 | 2063 |
| 12 | 4957 |
| 13 | 11731 |
| 14 | 26329 |
| 15 | 59501 |
| 16 | 132273 |
| 17 | 294475 |
| 18 | 644557 |
| 19 | 1392933 |
| 20 | 2982557 |