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 | 13 |
| 2 | 43 |
| 3 | 143 |
| 4 | 479 |
| 5 | 1616 |
| 6 | 5492 |
| 7 | 18804 |
| 8 | 64869 |
| 9 | 225483 |
| 10 | 789747 |
| 11 | 2787100 |
| 12 | 9910252 |
| 13 | 35501416 |
| 14 | 128109313 |
| 15 | 465606659 |
| 16 | 1704022367 |
| 17 | 6278399432 |
| 18 | 23282368196 |
| 19 | 86873186508 |
| 20 | 326055377709 |
| 21 | 1230562324251 |
| 22 | 4668500002491 |
| 23 | 17797745988388 |