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 | 1 |
| 3 | 3 |
| 4 | 7 |
| 5 | 24 |
| 6 | 49 |
| 7 | 205 |
| 8 | 411 |
| 9 | 1668 |
| 10 | 5011 |
| 11 | 20095 |
| 12 | 40191 |
| 13 | 241372 |
| 14 | 482745 |
| 15 | 1931393 |
| 16 | 7725627 |
| 17 | 38629803 |
| 18 | 77259607 |
| 19 | 463562851 |
| 20 | 927125703 |
| 21 | 5562774334 |
| 22 | 22251097753 |
| 23 | 89004431205 |
| 24 | 178008862411 |
| 25 | 1424071142304 |
| 26 | 4272213426961 |
| 27 | 17088854190591 |
| 28 | 68355416767375 |
| 29 | 410132502535664 |
| 30 | 820265005071329 |