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 | 3 |
| 2 | 9 |
| 3 | 27 |
| 4 | 82 |
| 5 | 242 |
| 6 | 736 |
| 7 | 2188 |
| 8 | 6600 |
| 9 | 19736 |
| 10 | 59328 |
| 11 | 177744 |
| 12 | 533728 |
| 13 | 1600160 |
| 14 | 4802560 |
| 15 | 14403520 |
| 16 | 43218816 |
| 17 | 129640064 |
| 18 | 388952832 |
| 19 | 1166793216 |
| 20 | 3500510464 |
| 21 | 10501269248 |
| 22 | 31504332544 |
| 23 | 94511948032 |
| 24 | 283537942272 |
| 25 | 850609632512 |