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 | 30 |
| 2 | 585 |
| 3 | 9450 |
| 4 | 137781 |
| 5 | 1888110 |
| 6 | 24862545 |
| 7 | 318755250 |
| 8 | 4012058061 |
| 9 | 49847787990 |
| 10 | 613622150505 |
| 11 | 7503229474650 |
| 12 | 91300979746341 |
| 13 | 1106997911204670 |
| 14 | 13386607046238465 |
| 15 | 161563913916523650 |