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 | 60 |
| 6 | 1701 |
| 7 | 14952 |
| 8 | 81228 |
| 9 | 331884 |
| 10 | 1116675 |
| 11 | 3256407 |
| 12 | 8500734 |
| 13 | 20306286 |
| 14 | 45093048 |
| 15 | 94189095 |
| 16 | 186736368 |
| 17 | 353904096 |
| 18 | 644842674 |
| 19 | 1134910242 |
| 20 | 1936817820 |
| 21 | 3215467584 |
| 22 | 5207403663 |
| 23 | 8245956642 |
| 24 | 12793342716 |
| 25 | 19481177100 |
| 26 | 29161079805 |
| 27 | 42967291185 |
| 28 | 62393475690 |