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 | 1 |
| 2 | 3 |
| 3 | 17 |
| 4 | 19 |
| 5 | 81 |
| 6 | 8351 |
| 7 | 184553 |
| 8 | 52907 |
| 9 | 1768847 |
| 10 | 70442753 |
| 11 | 1096172081 |
| 12 | 22198464713 |
| 13 | 195894185831 |
| 14 | 42653714271997 |
| 15 | 30188596935106763 |
| 16 | 20689743895700791 |
| 17 | 670597992748852241 |
| 18 | 71867806446352961329 |
| 19 | 8445943795439038164379 |
| 20 | 379371134635840861537 |