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 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 8 |
| 6 | 20 |
| 7 | 57 |
| 8 | 171 |
| 9 | 548 |
| 10 | 1894 |
| 11 | 6998 |
| 12 | 27368 |
| 13 | 112653 |
| 14 | 486645 |
| 15 | 2201162 |
| 16 | 10397944 |
| 17 | 51161168 |
| 18 | 261571460 |
| 19 | 1386846249 |
| 20 | 7612315023 |
| 21 | 43190917004 |
| 22 | 252951090586 |
| 23 | 1527112817054 |
| 24 | 9492126182336 |
| 25 | 60677428545165 |
| 26 | 398489257136529 |
| 27 | 2686088269505042 |
| 28 | 18567557376240748 |