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 | 3 |
| 1 | 14 |
| 2 | 62 |
| 3 | 273 |
| 4 | 1200 |
| 5 | 5271 |
| 6 | 23146 |
| 7 | 101626 |
| 8 | 446181 |
| 9 | 1958880 |
| 10 | 8600043 |
| 11 | 37756502 |
| 12 | 165760934 |
| 13 | 727733433 |
| 14 | 3194937360 |
| 15 | 14026596927 |
| 16 | 61580365906 |
| 17 | 270353629378 |
| 18 | 1186921889997 |
| 19 | 5210892012480 |
| 20 | 22877154557139 |
| 21 | 100436585338334 |
| 22 | 440942410322894 |
| 23 | 1935850452749409 |