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 | 1 |
| 2 | 9 |
| 3 | 36 |
| 4 | 72 |
| 5 | 188 |
| 6 | 688 |
| 7 | 2085 |
| 8 | 5497 |
| 9 | 16037 |
| 10 | 49553 |
| 11 | 144816 |
| 12 | 413800 |
| 13 | 1217824 |
| 14 | 3611968 |
| 15 | 10551977 |
| 16 | 30756729 |
| 17 | 90335433 |
| 18 | 265402081 |
| 19 | 776832420 |
| 20 | 2274331728 |
| 21 | 6670542132 |
| 22 | 19558546400 |
| 23 | 57298805509 |
| 24 | 167902287673 |
| 25 | 492193237461 |
| 26 | 1442605306409 |