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 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 28 |
| 5 | 78 |
| 6 | 1596 |
| 7 | 5995 |
| 8 | 67896 |
| 9 | 887778 |
| 10 | 15997996 |
| 11 | 398988876 |
| 12 | 9876799878 |
| 13 | 299789989975 |
| 14 | 35998897988976 |
| 15 | 589598998999878 |
| 16 | 78999997699698778 |
| 17 | 7987899888859999878 |
| 18 | 1998997979958978979995 |
| 19 | 539799799988999999688778 |