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 | 11 |
| 3 | 47 |
| 4 | 225 |
| 5 | 1159 |
| 6 | 6067 |
| 7 | 28419 |
| 8 | 58433 |
| 9 | -1390645 |
| 10 | -35514309 |
| 11 | -636045257 |
| 12 | -10431927839 |
| 13 | -167173905393 |
| 14 | -2678202265885 |
| 15 | -43236880758901 |
| 16 | -703702453254783 |
| 17 | -11485574113211501 |
| 18 | -185707408082199317 |
| 19 | -2901041900411825985 |