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 | 17 |
| 5 | 59 |
| 6 | 229 |
| 7 | 1029 |
| 8 | 5242 |
| 9 | 30040 |
| 10 | 191201 |
| 11 | 1338897 |
| 12 | 10228097 |
| 13 | 84647981 |
| 14 | 754437958 |
| 15 | 7204350870 |
| 16 | 73382899597 |
| 17 | 794189092567 |
| 18 | 9100736472725 |
| 19 | 110080467183393 |
| 20 | 1401588037032782 |
| 21 | 18737851806495008 |
| 22 | 262435512896178877 |