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 | 2 |
| 2 | 5 |
| 3 | 13 |
| 4 | 33 |
| 5 | 83 |
| 6 | 209 |
| 7 | 527 |
| 8 | 1329 |
| 9 | 3351 |
| 10 | 8449 |
| 11 | 21303 |
| 12 | 53713 |
| 13 | 135431 |
| 14 | 341473 |
| 15 | 860983 |
| 16 | 2170865 |
| 17 | 5473575 |
| 18 | 13800961 |
| 19 | 34797463 |
| 20 | 87737617 |
| 21 | 221219847 |
| 22 | 557779233 |
| 23 | 1406373239 |
| 24 | 3546000945 |
| 25 | 8940814823 |
| 26 | 22543189057 |
| 27 | 56839939415 |
| 28 | 143315069777 |