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 | 1 |
| 4 | 2 |
| 5 | 8 |
| 6 | 18 |
| 7 | 53 |
| 8 | 124 |
| 9 | 328 |
| 10 | 780 |
| 11 | 1969 |
| 12 | 4718 |
| 13 | 11648 |
| 14 | 28014 |
| 15 | 68405 |
| 16 | 164824 |
| 17 | 400240 |
| 18 | 965304 |
| 19 | 2337409 |
| 20 | 5640122 |
| 21 | 13637336 |
| 22 | 32914794 |
| 23 | 79525973 |
| 24 | 191966740 |
| 25 | 463636600 |
| 26 | 1119239940 |
| 27 | 2702647921 |
| 28 | 6524535782 |
| 29 | 15753313808 |
| 30 | 38031163398 |