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 | 2 |
| 3 | 4 |
| 4 | 12 |
| 5 | 43 |
| 6 | 160 |
| 7 | 668 |
| 8 | 3098 |
| 9 | 15465 |
| 10 | 83100 |
| 11 | 477651 |
| 12 | 2914505 |
| 13 | 18795814 |
| 14 | 127790544 |
| 15 | 911448954 |
| 16 | 6808162094 |
| 17 | 53067398065 |
| 18 | 430956571977 |
| 19 | 3636314065247 |
| 20 | 31841519540324 |
| 21 | 288664242344692 |
| 22 | 2706949104147162 |
| 23 | 26205222185730884 |
| 24 | 261681461422075548 |
| 25 | 2691088457402830312 |