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) |
|---|---|
| 6 | 1 |
| 7 | 28 |
| 8 | 399 |
| 9 | 4179 |
| 10 | 36498 |
| 11 | 282282 |
| 12 | 1999998 |
| 13 | 13258674 |
| 14 | 83417334 |
| 15 | 503090588 |
| 16 | 2929953026 |
| 17 | 16569715890 |
| 18 | 91386952020 |
| 19 | 493234934220 |
| 20 | 2612295374940 |
| 21 | 13607257868820 |
| 22 | 69841333755270 |
| 23 | 353777814426960 |
| 24 | 1770937330172010 |
| 25 | 8770508370593970 |
| 26 | 43015147164809820 |
| 27 | 209104302965011740 |