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) |
|---|---|
| 1 | -4 |
| 2 | -14 |
| 3 | 1561 |
| 4 | 25809 |
| 5 | 218769 |
| 6 | 1284261 |
| 7 | 5885671 |
| 8 | 22482031 |
| 9 | 74581507 |
| 10 | 220977757 |
| 11 | 596666070 |
| 12 | 1490430630 |
| 13 | 3484310310 |
| 14 | 7693206894 |
| 15 | 16160890914 |
| 16 | 32492871698 |
| 17 | 62838521438 |
| 18 | 117376191548 |
| 19 | 212507783895 |
| 20 | 374035542815 |
| 21 | 641676187295 |
| 22 | 1075368660795 |
| 23 | 1763954792145 |