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 | 21 |
| 3 | 273 |
| 4 | 10101 |
| 5 | 316407 |
| 6 | 6914271 |
| 7 | 2424626841 |
| 8 | 346084535811 |
| 9 | 6177672967557 |
| 10 | 1741866776384007 |
| 11 | 92264158181274807 |
| 12 | 103008522046409631057 |
| 13 | 22810816825458528984663 |
| 14 | 2220066397007943013450011 |
| 15 | 545889722100356705628041121 |
| 16 | 73293936170018923619553695493 |