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 | 26 |
| 4 | 64 |
| 5 | 152 |
| 6 | 352 |
| 7 | 800 |
| 8 | 1792 |
| 9 | 3968 |
| 10 | 8704 |
| 11 | 18944 |
| 12 | 40960 |
| 13 | 88064 |
| 14 | 188416 |
| 15 | 401408 |
| 16 | 851968 |
| 17 | 1802240 |
| 18 | 3801088 |
| 19 | 7995392 |
| 20 | 16777216 |
| 21 | 35127296 |
| 22 | 73400320 |
| 23 | 153092096 |
| 24 | 318767104 |
| 25 | 662700032 |
| 26 | 1375731712 |
| 27 | 2852126720 |
| 28 | 5905580032 |
| 29 | 12213813248 |
| 30 | 25232932864 |