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 | 3 |
| 3 | 9 |
| 4 | 29 |
| 5 | 97 |
| 6 | 333 |
| 7 | 1165 |
| 8 | 4135 |
| 9 | 14845 |
| 10 | 53791 |
| 11 | 196417 |
| 12 | 721887 |
| 13 | 2667941 |
| 14 | 9907851 |
| 15 | 36950465 |
| 16 | 138320021 |
| 17 | 519515209 |
| 18 | 1957091277 |
| 19 | 7392602917 |
| 20 | 27992976565 |
| 21 | 106236268337 |
| 22 | 404005515873 |
| 23 | 1539293204549 |
| 24 | 5875059106769 |
| 25 | 22459721336977 |