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 | 1 |
| 2 | 9 |
| 3 | 134 |
| 4 | 2331 |
| 5 | 41635 |
| 6 | 746604 |
| 7 | 13395941 |
| 8 | 240376941 |
| 9 | 4313380114 |
| 10 | 77400441855 |
| 11 | 1388894512391 |
| 12 | 24922700621784 |
| 13 | 447219716262409 |
| 14 | 8025032191009041 |
| 15 | 144003359719040030 |
| 16 | 2584035442744223139 |
| 17 | 46368634609657371691 |
| 18 | 832051387531037141316 |
| 19 | 14930556340948876798829 |