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 | 3 |
| 2 | 30 |
| 3 | 361 |
| 4 | 4887 |
| 5 | 71064 |
| 6 | 1084338 |
| 7 | 17127921 |
| 8 | 277691055 |
| 9 | 4594624095 |
| 10 | 77271742056 |
| 11 | 1317037554924 |
| 12 | 22699836814548 |
| 13 | 394961294853852 |
| 14 | 6928051002350154 |
| 15 | 122384261274499665 |
| 16 | 2175295243858562031 |
| 17 | 38875484049230706129 |
| 18 | 698131263508514451678 |