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 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 7 |
| 5 | 138 |
| 6 | 1878 |
| 7 | 23448 |
| 8 | 279286 |
| 9 | 3230577 |
| 10 | 36585097 |
| 11 | 407818620 |
| 12 | 4490844534 |
| 13 | 48972151631 |
| 14 | 529781669333 |
| 15 | 5693047157230 |
| 16 | 60832290450373 |
| 17 | 646862625625663 |
| 18 | 6849459596884350 |
| 19 | 72259172519243461 |