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 | 25 |
| 4 | 63 |
| 5 | 171 |
| 6 | 471 |
| 7 | 1193 |
| 8 | 3209 |
| 9 | 8841 |
| 10 | 22537 |
| 11 | 60393 |
| 12 | 165489 |
| 13 | 424451 |
| 14 | 1134849 |
| 15 | 3093893 |
| 16 | 7987289 |
| 17 | 21288933 |
| 18 | 57973543 |
| 19 | 150409931 |
| 20 | 399788279 |
| 21 | 1085870421 |
| 22 | 2831439537 |
| 23 | 7501994181 |
| 24 | 20330726077 |
| 25 | 53274740933 |
| 26 | 140615421393 |
| 27 | 380366331549 |
| 28 | 1002078031627 |
| 29 | 2634444052559 |