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 | 4 |
| 4 | 13 |
| 5 | 31 |
| 6 | 79 |
| 7 | 232 |
| 8 | 673 |
| 9 | 1891 |
| 10 | 5401 |
| 11 | 15742 |
| 12 | 45958 |
| 13 | 134122 |
| 14 | 393394 |
| 15 | 1159432 |
| 16 | 3425101 |
| 17 | 10137985 |
| 18 | 30079405 |
| 19 | 89437960 |
| 20 | 266389615 |
| 21 | 794667325 |
| 22 | 2374097485 |
| 23 | 7102303240 |
| 24 | 21272892055 |
| 25 | 63788000461 |
| 26 | 191471030791 |
| 27 | 575287348546 |
| 28 | 1730027151334 |
| 29 | 5206918491298 |