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) |
|---|---|
| 3 | 1 |
| 4 | 11 |
| 5 | 82 |
| 6 | 519 |
| 7 | 3010 |
| 8 | 16563 |
| 9 | 88092 |
| 10 | 457800 |
| 11 | 2340519 |
| 12 | 11824761 |
| 13 | 59217488 |
| 14 | 294596574 |
| 15 | 1458173626 |
| 16 | 7189542273 |
| 17 | 35341573246 |
| 18 | 173322863748 |
| 19 | 848473455491 |
| 20 | 4147736942919 |
| 21 | 20254228370249 |
| 22 | 98824420111063 |
| 23 | 481889327547656 |