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 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 13 |
| 6 | 41 |
| 7 | 104 |
| 8 | 326 |
| 9 | 958 |
| 10 | 3096 |
| 11 | 9958 |
| 12 | 33869 |
| 13 | 116806 |
| 14 | 417741 |
| 15 | 1526499 |
| 16 | 5732931 |
| 17 | 22015642 |
| 18 | 86543717 |
| 19 | 347495480 |
| 20 | 1424832602 |
| 21 | 5959123908 |
| 22 | 25407212843 |
| 23 | 110344848622 |
| 24 | 487879651220 |
| 25 | 2194697288628 |
| 26 | 10039367091586 |
| 27 | 46675057440634 |
| 28 | 220447539120814 |