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 | 76 |
| 4 | -106 |
| 5 | 1788 |
| 6 | -1516 |
| 7 | 57176 |
| 8 | -276634 |
| 9 | 2270444 |
| 10 | -10094212 |
| 11 | 97699752 |
| 12 | -664173444 |
| 13 | 4819718488 |
| 14 | -33236872088 |
| 15 | 259931360688 |
| 16 | -1894783205754 |
| 17 | 13983087008588 |
| 18 | -103270227527444 |
| 19 | 779496572387208 |
| 20 | -5855545477963244 |
| 21 | 44016069418771976 |
| 22 | -331519650617078376 |
| 23 | 2514477954420678352 |