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 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 20 |
| 5 | 46 |
| 6 | 96 |
| 7 | 204 |
| 8 | 420 |
| 9 | 864 |
| 10 | 1752 |
| 11 | 3520 |
| 12 | 7068 |
| 13 | 14160 |
| 14 | 28360 |
| 15 | 56736 |
| 16 | 113508 |
| 17 | 227040 |
| 18 | 454176 |
| 19 | 908424 |
| 20 | 1816944 |
| 21 | 3633908 |
| 22 | 7267828 |
| 23 | 14535662 |
| 24 | 29071328 |
| 25 | 58142704 |
| 26 | 116285418 |
| 27 | 232570884 |
| 28 | 465141864 |
| 29 | 930283760 |
| 30 | 1860567600 |