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 | 0 |
| 1 | 5 |
| 2 | 70 |
| 3 | 985 |
| 4 | 13860 |
| 5 | 195025 |
| 6 | 2744210 |
| 7 | 38613965 |
| 8 | 543339720 |
| 9 | 7645370045 |
| 10 | 107578520350 |
| 11 | 1513744654945 |
| 12 | 21300003689580 |
| 13 | 299713796309065 |
| 14 | 4217293152016490 |
| 15 | 59341817924539925 |
| 16 | 835002744095575440 |
| 17 | 11749380235262596085 |
| 18 | 165326326037771920630 |
| 19 | 2326317944764069484905 |