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 | -3 |
| 2 | 5 |
| 3 | -8 |
| 4 | 14 |
| 5 | -25 |
| 6 | 44 |
| 7 | -77 |
| 8 | 135 |
| 9 | -237 |
| 10 | 416 |
| 11 | -730 |
| 12 | 1281 |
| 13 | -2248 |
| 14 | 3945 |
| 15 | -6923 |
| 16 | 12149 |
| 17 | -21320 |
| 18 | 37414 |
| 19 | -65657 |
| 20 | 115220 |
| 21 | -202197 |
| 22 | 354831 |
| 23 | -622685 |
| 24 | 1092736 |
| 25 | -1917618 |
| 26 | 3365185 |
| 27 | -5905488 |
| 28 | 10363409 |
| 29 | -18186515 |
| 30 | 31915109 |
| 31 | -56007112 |
| 32 | 98285630 |
| 33 | -172479257 |
| 34 | 302679996 |
| 35 | -531166365 |
| 36 | 932131991 |