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) |
|---|---|
| 1 | 10 |
| 2 | -90 |
| 3 | -1090 |
| 4 | 8910 |
| 5 | -91090 |
| 6 | 908910 |
| 7 | -9091090 |
| 8 | 90908910 |
| 9 | 1090908910 |
| 10 | 11090908910 |
| 11 | -88909091090 |
| 12 | 911090908910 |
| 13 | -9088909091090 |
| 14 | 90911090908910 |
| 15 | 1090911090908910 |
| 16 | 11090911090908910 |
| 17 | -88909088909091090 |
| 18 | 911090911090908910 |
| 19 | -9088909088909091090 |