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 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 15 |
| 5 | 34 |
| 6 | 83 |
| 7 | 198 |
| 8 | 488 |
| 9 | 1202 |
| 10 | 3015 |
| 11 | 7608 |
| 12 | 19432 |
| 13 | 49994 |
| 14 | 129779 |
| 15 | 339176 |
| 16 | 892600 |
| 17 | 2362634 |
| 18 | 6288156 |
| 19 | 16816232 |
| 20 | 45170466 |
| 21 | 121812152 |
| 22 | 329679487 |
| 23 | 895171236 |
| 24 | 2437885058 |
| 25 | 6657311202 |
| 26 | 18224979884 |
| 27 | 50006899724 |
| 28 | 137502724754 |