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 | 180 |
| 2 | 1269 |
| 3 | 5940 |
| 4 | 20454 |
| 5 | 140470 |
| 6 | 304548 |
| 7 | 605685 |
| 8 | 1965462 |
| 9 | 5261278 |
| 10 | 17967252 |
| 11 | 25736406 |
| 12 | 49799782 |
| 13 | 155060070 |
| 14 | 254724622 |
| 15 | 402876885 |
| 16 | 616803846 |
| 17 | 918048406 |
| 18 | 1109465220 |
| 19 | 2638932670 |
| 20 | 4871761782 |
| 21 | 6475385158 |
| 22 | 11018543046 |
| 23 | 14135549422 |
| 24 | 22598655270 |
| 25 | 42920128086 |