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 | 2 |
| 2 | 5 |
| 3 | 22 |
| 4 | 75 |
| 5 | 264 |
| 6 | 941 |
| 7 | 3286 |
| 8 | 11623 |
| 9 | 40960 |
| 10 | 144267 |
| 11 | 508812 |
| 12 | 1792981 |
| 13 | 6319994 |
| 14 | 22277291 |
| 15 | 78518760 |
| 16 | 276763545 |
| 17 | 975517878 |
| 18 | 3438444583 |
| 19 | 12119670866 |
| 20 | 42718700667 |
| 21 | 150572583140 |
| 22 | 530730064095 |
| 23 | 1870688029160 |
| 24 | 6593699432859 |
| 25 | 23241110692298 |
| 26 | 81918995835971 |