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) |
|---|---|
| 4 | 1 |
| 5 | 5 |
| 6 | 25 |
| 7 | 134 |
| 8 | 815 |
| 9 | 5657 |
| 10 | 44549 |
| 11 | 394266 |
| 12 | 3883182 |
| 13 | 42174500 |
| 14 | 500942458 |
| 15 | 6460077110 |
| 16 | 89875729761 |
| 17 | 1341559805867 |
| 18 | 21382747361727 |
| 19 | 362402701510514 |
| 20 | 6507348542427217 |
| 21 | 123394642353693319 |
| 22 | 2463866954996239829 |
| 23 | 51670868533003154264 |
| 24 | 1135456889195715187948 |