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 | 3 |
| 2 | 9 |
| 3 | 24 |
| 4 | 62 |
| 5 | 154 |
| 6 | 376 |
| 7 | 902 |
| 8 | 2142 |
| 9 | 5040 |
| 10 | 11786 |
| 11 | 27418 |
| 12 | 63544 |
| 13 | 146822 |
| 14 | 338478 |
| 15 | 778944 |
| 16 | 1790282 |
| 17 | 4110730 |
| 18 | 9432424 |
| 19 | 21633542 |
| 20 | 49603134 |
| 21 | 113717328 |
| 22 | 260691722 |
| 23 | 597649402 |
| 24 | 1370287384 |
| 25 | 3142264070 |
| 26 | 7206988878 |
| 27 | 16533117792 |
| 28 | 37935980618 |
| 29 | 87065571946 |