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 | 1 |
| 2 | 5 |
| 3 | 40 |
| 4 | 450 |
| 5 | 6370 |
| 6 | 104498 |
| 7 | 1843324 |
| 8 | 33778574 |
| 9 | 632053347 |
| 10 | 11983323029 |
| 11 | 229304019611 |
| 12 | 4419024507187 |
| 13 | 85653324334312 |
| 14 | 1668284177327594 |
| 15 | 32629561950146399 |