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 | 0 |
| 3 | -1 |
| 4 | 0 |
| 5 | 7 |
| 6 | 28 |
| 7 | 79 |
| 8 | 192 |
| 9 | 431 |
| 10 | 924 |
| 11 | 1927 |
| 12 | 3952 |
| 13 | 8023 |
| 14 | 16188 |
| 15 | 32543 |
| 16 | 65280 |
| 17 | 130783 |
| 18 | 261820 |
| 19 | 523927 |
| 20 | 1048176 |
| 21 | 2096711 |
| 22 | 4193820 |
| 23 | 8388079 |
| 24 | 16776640 |
| 25 | 33553807 |
| 26 | 67108188 |
| 27 | 134216999 |
| 28 | 268434672 |
| 29 | 536870071 |
| 30 | 1073740924 |
| 31 | 2147482687 |
| 32 | 4294966272 |
| 33 | 8589933503 |
| 34 | 17179868028 |
| 35 | 34359737143 |