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 | 3 |
| 2 | 14 |
| 3 | 94 |
| 4 | 735 |
| 5 | 6239 |
| 6 | 55888 |
| 7 | 520028 |
| 8 | 4977321 |
| 9 | 48689260 |
| 10 | 484623552 |
| 11 | 4892304686 |
| 12 | 49971163021 |
| 13 | 515496741918 |
| 14 | 5363023614620 |
| 15 | 56204877993184 |
| 16 | 592811175777029 |
| 17 | 6287909183751105 |
| 18 | 67029933733468729 |
| 19 | 717749621979800340 |
| 20 | 7716543390041275964 |