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 | 13 |
| 2 | 273 |
| 3 | 4641 |
| 4 | 85085 |
| 5 | 1514513 |
| 6 | 27261234 |
| 7 | 488605194 |
| 8 | 8771626578 |
| 9 | 157373300370 |
| 10 | 2824135408458 |
| 11 | 50675778059634 |
| 12 | 909348684070099 |
| 13 | 16317540120588343 |
| 14 | 292806787575013635 |
| 15 | 5254201798026392211 |
| 16 | 94282845030238533383 |
| 17 | 1691836875411111866723 |
| 18 | 30358781826262552258596 |