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) |
|---|---|
| 2 | 2 |
| 3 | 8 |
| 4 | 48 |
| 5 | 98 |
| 6 | 350 |
| 7 | 440 |
| 8 | 2430 |
| 9 | 2430 |
| 10 | 13310 |
| 11 | 13454 |
| 12 | 17575 |
| 13 | 212380 |
| 14 | 212380 |
| 15 | 212380 |
| 16 | 1205644 |
| 17 | 1205644 |
| 18 | 1205644 |
| 19 | 2018978 |
| 20 | 3939648 |
| 21 | 3939648 |
| 22 | 15473808 |
| 23 | 15473808 |
| 24 | 407498958 |
| 25 | 407498958 |
| 26 | 407498958 |
| 27 | 138982582998 |
| 28 | 138982582998 |
| 29 | 138982582998 |
| 30 | 138982582998 |