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 | 7 |
| 2 | 357 |
| 3 | 17857 |
| 4 | 892857 |
| 5 | 44642857 |
| 6 | 2232 |
| 7 | 111607 |
| 8 | 5580357 |
| 9 | 279017857 |
| 10 | 13950892857 |
| 11 | 697544642857 |
| 12 | 34877232 |
| 13 | 1743861607 |
| 14 | 87193080357 |
| 15 | 4359654017857 |
| 16 | 217982700892857 |
| 17 | 10899135044642857 |
| 18 | 544956752232 |
| 19 | 27247837611607 |