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 | 1 |
| 2 | 1 |
| 3 | -2 |
| 4 | -5 |
| 5 | 1 |
| 6 | 16 |
| 7 | 94 |
| 8 | 127 |
| 9 | -317 |
| 10 | -1103 |
| 11 | -2258 |
| 12 | 160 |
| 13 | 18922 |
| 14 | 39664 |
| 15 | -163064 |
| 16 | -524489 |
| 17 | -187577 |
| 18 | 1711591 |
| 19 | 12353800 |
| 20 | 18926119 |
| 21 | -53449661 |
| 22 | -207918068 |
| 23 | -15689834 |
| 24 | 960812728 |
| 25 | 3295064650 |
| 26 | 3870965368 |
| 27 | -33248209286 |
| 28 | -96830084768 |
| 29 | 17122290256 |
| 30 | 505711364524 |