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 | 3 |
| 2 | 8 |
| 3 | 20 |
| 4 | 52 |
| 5 | 121 |
| 6 | 301 |
| 7 | 675 |
| 8 | 1628 |
| 9 | 3570 |
| 10 | 8426 |
| 11 | 18202 |
| 12 | 42288 |
| 13 | 90374 |
| 14 | 207464 |
| 15 | 439800 |
| 16 | 1000194 |
| 17 | 2106961 |
| 18 | 4755715 |
| 19 | 9967599 |
| 20 | 22359788 |
| 21 | 46670273 |
| 22 | 104154703 |
| 23 | 216643945 |
| 24 | 481381746 |
| 25 | 998346275 |
| 26 | 2210037191 |
| 27 | 4571884119 |
| 28 | 10088030640 |