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 | 5 |
| 2 | 1515 |
| 3 | 457525 |
| 4 | 138171035 |
| 5 | 41727195045 |
| 6 | 12601474732555 |
| 7 | 3805603642036565 |
| 8 | 1149279698420310075 |
| 9 | 347078663319291606085 |
| 10 | 104816607042727644727595 |
| 11 | 31654268248240429416127605 |
| 12 | 9559484194361566956025809115 |
| 13 | 2886932572428944980290378225125 |