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 | 11 |
| 2 | -29 |
| 3 | -189 |
| 4 | 451 |
| 5 | 3011 |
| 6 | -7229 |
| 7 | -48189 |
| 8 | 115651 |
| 9 | 771011 |
| 10 | -1850429 |
| 11 | -12336189 |
| 12 | 29606851 |
| 13 | 197379011 |
| 14 | -473709629 |
| 15 | -3158064189 |
| 16 | 7579354051 |
| 17 | 50529027011 |
| 18 | -121269664829 |
| 19 | -808464432189 |
| 20 | 1940314637251 |
| 21 | 12935430915011 |
| 22 | -31045034196029 |
| 23 | -206966894640189 |