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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 76 |
| 9 | 438 |
| 10 | 1846 |
| 11 | 6664 |
| 12 | 22322 |
| 13 | 71223 |
| 14 | 221747 |
| 15 | 685899 |
| 16 | 2133273 |
| 17 | 6639848 |
| 18 | 20631028 |
| 19 | 63857132 |
| 20 | 196698620 |
| 21 | 602652416 |
| 22 | 1837237916 |
| 23 | 5577247428 |
| 24 | 16876196404 |
| 25 | 50936285192 |
| 26 | 153419520771 |
| 27 | 461274617487 |
| 28 | 1384650408582 |
| 29 | 4150200289940 |
| 30 | 12421725164955 |