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 | 9 |
| 4 | 112 |
| 5 | 1004 |
| 6 | 6404 |
| 7 | 32890 |
| 8 | 137528 |
| 9 | 499641 |
| 10 | 1579113 |
| 11 | 4551268 |
| 12 | 11861187 |
| 13 | 29034355 |
| 14 | 65777365 |
| 15 | 142805210 |
| 16 | 291148080 |
| 17 | 576393509 |
| 18 | 1082580072 |
| 19 | 1993354411 |
| 20 | 3505999065 |
| 21 | 6088877416 |
| 22 | 10148269838 |
| 23 | 16796812567 |
| 24 | 26776385524 |
| 25 | 42563703291 |