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 | 7 |
| 2 | 140 |
| 3 | 2100 |
| 4 | 28000 |
| 5 | 350000 |
| 6 | 4200000 |
| 7 | 49000000 |
| 8 | 560000000 |
| 9 | 6300000000 |
| 10 | 70000000000 |
| 11 | 770000000000 |
| 12 | 8400000000000 |
| 13 | 91000000000000 |
| 14 | 980000000000000 |
| 15 | 10500000000000000 |
| 16 | 112000000000000000 |
| 17 | 1190000000000000000 |
| 18 | 12600000000000000000 |
| 19 | 133000000000000000000 |