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 | 15 |
| 2 | 135 |
| 3 | 1215 |
| 4 | 11295 |
| 5 | 107775 |
| 6 | 1046655 |
| 7 | 10279935 |
| 8 | 101679615 |
| 9 | 1010077695 |
| 10 | 10060466175 |
| 11 | 100362797055 |
| 12 | 1002176782335 |
| 13 | 10013060694015 |
| 14 | 100078364164095 |
| 15 | 1000470184984575 |
| 16 | 10002821109907455 |
| 17 | 100016926659444735 |