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 | 2 |
| 3 | 6 |
| 4 | 22 |
| 5 | 89 |
| 6 | 381 |
| 7 | 1694 |
| 8 | 7744 |
| 9 | 36168 |
| 10 | 171831 |
| 11 | 827814 |
| 12 | 4034589 |
| 13 | 19857262 |
| 14 | 98555324 |
| 15 | 492710856 |
| 16 | 2478897620 |
| 17 | 12541604830 |
| 18 | 63768192378 |
| 19 | 325674039636 |
| 20 | 1669922290311 |
| 21 | 8593644472017 |
| 22 | 44369362778645 |
| 23 | 229767801472366 |
| 24 | 1193126351099007 |
| 25 | 6211253430642091 |