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 | 1 |
| 5 | 3 |
| 6 | 9 |
| 7 | 23 |
| 8 | 60 |
| 9 | 150 |
| 10 | 354 |
| 11 | 843 |
| 12 | 1983 |
| 13 | 4608 |
| 14 | 10638 |
| 15 | 24318 |
| 16 | 55043 |
| 17 | 123862 |
| 18 | 276868 |
| 19 | 614996 |
| 20 | 1359446 |
| 21 | 2990726 |
| 22 | 6550528 |
| 23 | 14292132 |
| 24 | 31069860 |
| 25 | 67316446 |
| 26 | 145403700 |
| 27 | 313177200 |
| 28 | 672746880 |
| 29 | 1441600632 |
| 30 | 3082042512 |
| 31 | 6575014400 |
| 32 | 13998418584 |
| 33 | 29746639512 |