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 | 0 |
| 1 | 2 |
| 2 | 5 |
| 3 | 12 |
| 4 | 37 |
| 5 | 158 |
| 6 | 879 |
| 7 | 5920 |
| 8 | 46241 |
| 9 | 409122 |
| 10 | 4037923 |
| 11 | 43954724 |
| 12 | 522956325 |
| 13 | 6749977126 |
| 14 | 93928268327 |
| 15 | 1401602636328 |
| 16 | 22324392524329 |
| 17 | 378011820620330 |
| 18 | 6780385526348331 |
| 19 | 128425485935180332 |
| 20 | 2561327494111820333 |