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 | 3 |
| 4 | 6 |
| 5 | 16 |
| 6 | 43 |
| 7 | 116 |
| 8 | 329 |
| 9 | 947 |
| 10 | 2762 |
| 11 | 8176 |
| 12 | 24469 |
| 13 | 73896 |
| 14 | 224960 |
| 15 | 689623 |
| 16 | 2126947 |
| 17 | 6595273 |
| 18 | 20548732 |
| 19 | 64298032 |
| 20 | 201969823 |
| 21 | 636639087 |
| 22 | 2013174695 |
| 23 | 6384574754 |
| 24 | 20302081620 |
| 25 | 64716553655 |
| 26 | 206764068578 |
| 27 | 661983640080 |
| 28 | 2123573339921 |
| 29 | 6824597707820 |
| 30 | 21969711674581 |