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 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 22 |
| 6 | 91 |
| 7 | 406 |
| 8 | 1896 |
| 9 | 9093 |
| 10 | 44279 |
| 11 | 217500 |
| 12 | 1073657 |
| 13 | 5314870 |
| 14 | 26352107 |
| 15 | 130778039 |
| 16 | 649352929 |
| 17 | 3225196431 |
| 18 | 16021584848 |
| 19 | 79597062632 |
| 20 | 395469296912 |
| 21 | 1964908443531 |
| 22 | 9762920818182 |
| 23 | 48508934285620 |
| 24 | 241027326818991 |
| 25 | 1197601448443963 |
| 26 | 5950578465799856 |