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 | 7 |
| 2 | 49 |
| 3 | 322 |
| 4 | 2072 |
| 5 | 13216 |
| 6 | 83972 |
| 7 | 532840 |
| 8 | 3381860 |
| 9 | 21491464 |
| 10 | 136856180 |
| 11 | 873803848 |
| 12 | 5596638788 |
| 13 | 35973158152 |
| 14 | 232118471828 |
| 15 | 1503949949896 |
| 16 | 9786663686756 |
| 17 | 63969334316680 |
| 18 | 420026972347316 |
| 19 | 2770499256109384 |
| 20 | 18356852895660164 |