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 | 7 |
| 2 | 65 |
| 3 | 743 |
| 4 | 9921 |
| 5 | 150151 |
| 6 | 2526593 |
| 7 | 46615783 |
| 8 | 933072513 |
| 9 | 20093861895 |
| 10 | 462440842177 |
| 11 | 11310514854375 |
| 12 | 292627518129985 |
| 13 | 7976748158144647 |
| 14 | 228308400790500097 |
| 15 | 6840702405678586343 |
| 16 | 214000748166439723265 |
| 17 | 6973447420429351808007 |
| 18 | 236204029044752265931585 |
| 19 | 8300724166287243795922151 |