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 | 6 |
| 3 | 16 |
| 4 | 38 |
| 5 | 88 |
| 6 | 196 |
| 7 | 420 |
| 8 | 878 |
| 9 | 1794 |
| 10 | 3584 |
| 11 | 7032 |
| 12 | 13572 |
| 13 | 25792 |
| 14 | 48352 |
| 15 | 89512 |
| 16 | 163774 |
| 17 | 296444 |
| 18 | 531234 |
| 19 | 943072 |
| 20 | 1659560 |
| 21 | 2896376 |
| 22 | 5015700 |
| 23 | 8622108 |
| 24 | 14718652 |
| 25 | 24960138 |
| 26 | 42062200 |
| 27 | 70458160 |
| 28 | 117349856 |
| 29 | 194381704 |
| 30 | 320295312 |
| 31 | 525123604 |