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 | 3 |
| 1 | 18 |
| 2 | 234 |
| 3 | 1110 |
| 4 | 15018 |
| 5 | 70998 |
| 6 | 961194 |
| 7 | 4543830 |
| 8 | 61516458 |
| 9 | 290805078 |
| 10 | 3937053354 |
| 11 | 18611524950 |
| 12 | 251971414698 |
| 13 | 1191137596758 |
| 14 | 16126170540714 |
| 15 | 76232806192470 |
| 16 | 1032074914605738 |
| 17 | 4878899596318038 |
| 18 | 66052794534767274 |
| 19 | 312249574164354390 |