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 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 3 |
| 6 | 4 |
| 7 | 18 |
| 8 | 45 |
| 9 | 72 |
| 10 | 153 |
| 11 | 450 |
| 12 | 1066 |
| 13 | 2172 |
| 14 | 5142 |
| 15 | 13381 |
| 16 | 31752 |
| 17 | 72333 |
| 18 | 176475 |
| 19 | 441909 |
| 20 | 1065528 |
| 21 | 2551465 |
| 22 | 6292857 |
| 23 | 15620439 |
| 24 | 38229235 |
| 25 | 93698523 |
| 26 | 232545105 |
| 27 | 578019090 |
| 28 | 1430290512 |
| 29 | 3548336724 |
| 30 | 8851036863 |
| 31 | 22092054588 |
| 32 | 55093739760 |
| 33 | 137681640450 |