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) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | 9 |
| 8 | 53 |
| 9 | 261 |
| 10 | 1165 |
| 11 | 4887 |
| 12 | 19642 |
| 13 | 76519 |
| 14 | 291095 |
| 15 | 1086946 |
| 16 | 3998430 |
| 17 | 14530223 |
| 18 | 52272218 |
| 19 | 186467253 |
| 20 | 660449671 |
| 21 | 2325124444 |
| 22 | 8143334776 |
| 23 | 28393762841 |
| 24 | 98621419068 |
| 25 | 341403900888 |
| 26 | 1178425064256 |
| 27 | 4057244213071 |
| 28 | 13937739553781 |
| 29 | 47786215201214 |
| 30 | 163554669548711 |