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 | 1 |
| 6 | 6 |
| 7 | 21 |
| 8 | 56 |
| 9 | 126 |
| 10 | 252 |
| 11 | 462 |
| 12 | 792 |
| 13 | 1287 |
| 14 | 2002 |
| 15 | 3003 |
| 16 | 4368 |
| 17 | 6188 |
| 18 | 8568 |
| 19 | 11628 |
| 20 | 15504 |
| 21 | 20349 |
| 22 | 26334 |
| 23 | 33649 |
| 24 | 42504 |
| 25 | 53130 |
| 26 | 65780 |
| 27 | 80730 |
| 28 | 98280 |
| 29 | 118755 |
| 30 | 142506 |
| 31 | 169911 |
| 32 | 201376 |
| 33 | 237336 |
| 34 | 278256 |
| 35 | 324632 |
| 36 | 376992 |
| 37 | 435897 |
| 38 | 501942 |
| 39 | 575757 |
| 40 | 658008 |
| 41 | 749398 |