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 | 1 |
| 4 | 7 |
| 5 | 39 |
| 6 | 188 |
| 7 | 884 |
| 8 | 4116 |
| 9 | 19108 |
| 10 | 89926 |
| 11 | 427386 |
| 12 | 2068934 |
| 13 | 10163358 |
| 14 | 50888024 |
| 15 | 258983668 |
| 16 | 1342912608 |
| 17 | 7079970072 |
| 18 | 38000183102 |
| 19 | 207309599246 |
| 20 | 1150329076074 |
| 21 | 6484351459090 |
| 22 | 37143321514076 |
| 23 | 216001121263896 |
| 24 | 1275332898098744 |
| 25 | 7639400455469944 |
| 26 | 46423461664822648 |