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 | 1 |
| 2 | 19 |
| 3 | 155 |
| 4 | 936 |
| 5 | 4884 |
| 6 | 23465 |
| 7 | 107107 |
| 8 | 472600 |
| 9 | 2036838 |
| 10 | 8631206 |
| 11 | 36119798 |
| 12 | 149724940 |
| 13 | 616104450 |
| 14 | 2520629685 |
| 15 | 10265200035 |
| 16 | 41650094640 |
| 17 | 168481778790 |
| 18 | 679847488650 |
| 19 | 2737640364810 |
| 20 | 11005139655744 |
| 21 | 44176226269728 |
| 22 | 177114113623194 |
| 23 | 709364594864910 |
| 24 | 2838599638596176 |
| 25 | 11350436081373340 |