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 | 4 |
| 2 | 10 |
| 3 | 24 |
| 4 | 52 |
| 5 | 112 |
| 6 | 232 |
| 7 | 480 |
| 8 | 976 |
| 9 | 1984 |
| 10 | 4000 |
| 11 | 8064 |
| 12 | 16192 |
| 13 | 32512 |
| 14 | 65152 |
| 15 | 130560 |
| 16 | 261376 |
| 17 | 523264 |
| 18 | 1047040 |
| 19 | 2095104 |
| 20 | 4191232 |
| 21 | 8384512 |
| 22 | 16771072 |
| 23 | 33546240 |
| 24 | 67096576 |
| 25 | 134201344 |
| 26 | 268410880 |
| 27 | 536838144 |
| 28 | 1073692672 |
| 29 | 2147418112 |