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 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 20 |
| 5 | 72 |
| 6 | 244 |
| 7 | 968 |
| 8 | 3700 |
| 9 | 14792 |
| 10 | 58484 |
| 11 | 233928 |
| 12 | 932980 |
| 13 | 3731912 |
| 14 | 14916724 |
| 15 | 59666888 |
| 16 | 238623860 |
| 17 | 954495432 |
| 18 | 3817806964 |
| 19 | 15271227848 |
| 20 | 61084212340 |
| 21 | 244336849352 |
| 22 | 977344601204 |
| 23 | 3909378404808 |
| 24 | 15637502434420 |