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 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 12 |
| 6 | 32 |
| 7 | 87 |
| 8 | 251 |
| 9 | 733 |
| 10 | 2201 |
| 11 | 6696 |
| 12 | 20705 |
| 13 | 64681 |
| 14 | 204183 |
| 15 | 649738 |
| 16 | 2082939 |
| 17 | 6719063 |
| 18 | 21796084 |
| 19 | 71052001 |
| 20 | 232645645 |
| 21 | 764768959 |
| 22 | 2523033061 |
| 23 | 8350789334 |
| 24 | 27721841968 |
| 25 | 92277902858 |
| 26 | 307935654094 |
| 27 | 1029970333229 |
| 28 | 3452371784462 |
| 29 | 11595031966743 |