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 | 3 |
| 4 | 6 |
| 5 | 11 |
| 6 | 24 |
| 7 | 52 |
| 8 | 125 |
| 9 | 307 |
| 10 | 809 |
| 11 | 2190 |
| 12 | 6249 |
| 13 | 18348 |
| 14 | 56016 |
| 15 | 176272 |
| 16 | 571113 |
| 17 | 1906091 |
| 18 | 6517283 |
| 19 | 22879944 |
| 20 | 82144248 |
| 21 | 301617448 |
| 22 | 1131401427 |
| 23 | 4327790902 |
| 24 | 16886037207 |
| 25 | 67073179408 |
| 26 | 271242546501 |
| 27 | 1115489848809 |
| 28 | 4662462489619 |