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) |
|---|---|
| 5 | 1 |
| 6 | 5 |
| 7 | 21 |
| 8 | 81 |
| 9 | 296 |
| 10 | 1043 |
| 11 | 3585 |
| 12 | 12095 |
| 13 | 40221 |
| 14 | 132225 |
| 15 | 430633 |
| 16 | 1391623 |
| 17 | 4467689 |
| 18 | 14262766 |
| 19 | 45311977 |
| 20 | 143343279 |
| 21 | 451768405 |
| 22 | 1419092951 |
| 23 | 4444424613 |
| 24 | 13882255419 |
| 25 | 43256925753 |
| 26 | 134492621659 |
| 27 | 417322590000 |
| 28 | 1292554593007 |
| 29 | 3996626787973 |
| 30 | 12338508959035 |
| 31 | 38037021764053 |