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 | 6 |
| 2 | 29 |
| 3 | 133 |
| 4 | 597 |
| 5 | 2661 |
| 6 | 11856 |
| 7 | 52878 |
| 8 | 235986 |
| 9 | 1053345 |
| 10 | 4701627 |
| 11 | 20985035 |
| 12 | 93662073 |
| 13 | 418038721 |
| 14 | 1865820223 |
| 15 | 8327671681 |
| 16 | 37168717729 |
| 17 | 165894342774 |
| 18 | 740432630793 |
| 19 | 3304756826019 |
| 20 | 14750048986898 |
| 21 | 65833571645931 |
| 22 | 293833543748968 |
| 23 | 1311460845206801 |