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 | 3 |
| 1 | 13 |
| 2 | 65 |
| 3 | 349 |
| 4 | 1937 |
| 5 | 10933 |
| 6 | 62345 |
| 7 | 358189 |
| 8 | 2070497 |
| 9 | 12031333 |
| 10 | 70232825 |
| 11 | 411627229 |
| 12 | 2420927057 |
| 13 | 14281405333 |
| 14 | 84467696105 |
| 15 | 500702595469 |
| 16 | 2973697863617 |
| 17 | 17689599028933 |
| 18 | 105374654196185 |
| 19 | 628433226862909 |