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 | 1 |
| 1 | 4 |
| 2 | 26 |
| 3 | 204 |
| 4 | 1771 |
| 5 | 16380 |
| 6 | 158224 |
| 7 | 1577532 |
| 8 | 16112057 |
| 9 | 167710664 |
| 10 | 1772645420 |
| 11 | 18974357220 |
| 12 | 205263418941 |
| 13 | 2240623268512 |
| 14 | 24648785802336 |
| 15 | 272994644359580 |
| 16 | 3041495503591365 |
| 17 | 34064252968167180 |
| 18 | 383302465665133014 |