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 | 0 |
| 1 | 9 |
| 2 | 54 |
| 3 | 219 |
| 4 | 714 |
| 5 | 2001 |
| 6 | 5004 |
| 7 | 11439 |
| 8 | 24309 |
| 9 | 48619 |
| 10 | 92377 |
| 11 | 167959 |
| 12 | 293929 |
| 13 | 497419 |
| 14 | 817189 |
| 15 | 1307503 |
| 16 | 2042974 |
| 17 | 3124549 |
| 18 | 4686824 |
| 19 | 6906899 |
| 20 | 10015004 |
| 21 | 14307149 |
| 22 | 20160074 |
| 23 | 28048799 |
| 24 | 38567099 |
| 25 | 52451255 |
| 26 | 70607459 |
| 27 | 94143279 |