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) |
|---|---|
| 1 | 0 |
| 2 | 4 |
| 3 | 51 |
| 4 | 368 |
| 5 | 7310 |
| 6 | 301572 |
| 7 | 10893008 |
| 8 | 425004288 |
| 9 | 21411720954 |
| 10 | 1402042079000 |
| 11 | 105105019187432 |
| 12 | 8635626858155904 |
| 13 | 799519643414632478 |
| 14 | 84867202351157123016 |
| 15 | 10156012624316961798300 |
| 16 | 1341516630604157917448192 |
| 17 | 194184270583421507775461426 |
| 18 | 30809161255439152269369310392 |