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 | 0 |
| 1 | 1 |
| 2 | 21 |
| 3 | 331 |
| 4 | 4641 |
| 5 | 61051 |
| 6 | 771561 |
| 7 | 9487171 |
| 8 | 14358881 |
| 9 | 357947691 |
| 10 | 5937424601 |
| 11 | 85311670611 |
| 12 | 138428376721 |
| 13 | 4522712143931 |
| 14 | 79749833583241 |
| 15 | 177248169415651 |
| 16 | 5949729863572161 |
| 17 | 5447028499293771 |
| 18 | 559917313492231481 |