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 | 21 |
| 2 | 217 |
| 3 | 1498 |
| 4 | 7910 |
| 5 | 34566 |
| 6 | 131446 |
| 7 | 449732 |
| 8 | 1416513 |
| 9 | 4174765 |
| 10 | 11651717 |
| 11 | 31075422 |
| 12 | 79751854 |
| 13 | 198036146 |
| 14 | 477899790 |
| 15 | 1124785648 |
| 16 | 2589534248 |
| 17 | 5845989156 |
| 18 | 12968091584 |
| 19 | 28316428700 |
| 20 | 60953528230 |
| 21 | 129515454530 |
| 22 | 271955244610 |
| 23 | 564879359940 |
| 24 | 1161646929275 |
| 25 | 2366938010983 |
| 26 | 4781794056543 |