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 | 49 |
| 3 | 2353 |
| 4 | 112945 |
| 5 | 5421361 |
| 6 | 260225329 |
| 7 | 12490815793 |
| 8 | 599559158065 |
| 9 | 28778839587121 |
| 10 | 1381384300181809 |
| 11 | 66306446408726833 |
| 12 | 3182709427618887985 |
| 13 | 152770052525706623281 |
| 14 | 7332962521233917917489 |
| 15 | 351982201019228060039473 |
| 16 | 16895145648922946881894705 |
| 17 | 810966991148301450330945841 |