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) |
|---|---|
| 3 | 1 |
| 4 | 0 |
| 5 | 2 |
| 6 | 5 |
| 7 | 11 |
| 8 | 28 |
| 9 | 78 |
| 10 | 201 |
| 11 | 532 |
| 12 | 1441 |
| 13 | 3895 |
| 14 | 10569 |
| 15 | 28926 |
| 16 | 79493 |
| 17 | 219226 |
| 18 | 607189 |
| 19 | 1687880 |
| 20 | 4706737 |
| 21 | 13165215 |
| 22 | 36929595 |
| 23 | 103860429 |
| 24 | 292808814 |
| 25 | 827392709 |
| 26 | 2342964435 |
| 27 | 6647953886 |
| 28 | 18898472568 |
| 29 | 53818654942 |
| 30 | 153518738980 |
| 31 | 438602656951 |
| 32 | 1254943919799 |
| 33 | 3595714927194 |