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 | 2 |
| 2 | -2 |
| 3 | -8 |
| 4 | 6 |
| 5 | 42 |
| 6 | -8 |
| 7 | -228 |
| 8 | -90 |
| 9 | 1210 |
| 10 | 1238 |
| 11 | -6116 |
| 12 | -10864 |
| 13 | 28574 |
| 14 | 80932 |
| 15 | -116248 |
| 16 | -548010 |
| 17 | 339678 |
| 18 | 3455686 |
| 19 | 173208 |
| 20 | -20452674 |
| 21 | -14036418 |
| 22 | 113365140 |
| 23 | 156407916 |
| 24 | -580805472 |
| 25 | -1312098918 |
| 26 | 2659610562 |
| 27 | 9621079540 |
| 28 | -9902139124 |
| 29 | -64566648122 |
| 30 | 18521111032 |