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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 5 |
| 7 | 10 |
| 8 | 30 |
| 9 | 76 |
| 10 | 219 |
| 11 | 582 |
| 12 | 1662 |
| 13 | 4614 |
| 14 | 13080 |
| 15 | 36903 |
| 16 | 105098 |
| 17 | 298689 |
| 18 | 852734 |
| 19 | 2434660 |
| 20 | 6964349 |
| 21 | 19931147 |
| 22 | 57100177 |
| 23 | 163647811 |
| 24 | 469290004 |
| 25 | 1346225668 |
| 26 | 3863239150 |
| 27 | 11089085961 |
| 28 | 31838349956 |
| 29 | 91430943515 |
| 30 | 262615909503 |
| 31 | 754439588007 |
| 32 | 2167711283560 |