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 | 19 |
| 2 | 307 |
| 3 | 4915 |
| 4 | 78643 |
| 5 | 1258291 |
| 6 | 20132659 |
| 7 | 322122547 |
| 8 | 5153960755 |
| 9 | 82463372083 |
| 10 | 1319413953331 |
| 11 | 21110623253299 |
| 12 | 337769972052787 |
| 13 | 5404319552844595 |
| 14 | 86469112845513523 |
| 15 | 1383505805528216371 |
| 16 | 22136092888451461939 |
| 17 | 354177486215223391027 |
| 18 | 5666839779443574256435 |
| 19 | 90669436471097188102963 |
| 20 | 1450710983537555009647411 |