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 | 5 |
| 4 | 13 |
| 5 | 35 |
| 6 | 97 |
| 7 | 276 |
| 8 | 805 |
| 9 | 2404 |
| 10 | 7343 |
| 11 | 22916 |
| 12 | 72980 |
| 13 | 236857 |
| 14 | 782275 |
| 15 | 2625265 |
| 16 | 8938718 |
| 17 | 30834165 |
| 18 | 107608097 |
| 19 | 379454447 |
| 20 | 1350434278 |
| 21 | 4845475311 |
| 22 | 17512579630 |
| 23 | 63703732426 |
| 24 | 233063976059 |
| 25 | 857067469749 |
| 26 | 3166309373615 |
| 27 | 11745982220846 |