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) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 3 |
| 4 | 11 |
| 5 | 33 |
| 6 | 145 |
| 7 | 747 |
| 8 | 4607 |
| 9 | 32873 |
| 10 | 266969 |
| 11 | 2431611 |
| 12 | 24554191 |
| 13 | 272289633 |
| 14 | 3289836257 |
| 15 | 43017800315 |
| 16 | 605289111695 |
| 17 | 9119314568457 |
| 18 | 146474344313977 |
| 19 | 2498617856687403 |