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 | 5 |
| 2 | 23 |
| 3 | 103 |
| 4 | 450 |
| 5 | 1932 |
| 6 | 8196 |
| 7 | 34468 |
| 8 | 143997 |
| 9 | 598463 |
| 10 | 2476936 |
| 11 | 10216818 |
| 12 | 42023225 |
| 13 | 172436363 |
| 14 | 706132290 |
| 15 | 2886574198 |
| 16 | 11781962631 |
| 17 | 48025519977 |
| 18 | 195530083266 |
| 19 | 795241236228 |
| 20 | 3231290822280 |
| 21 | 13118557603984 |
| 22 | 53218706064038 |