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) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 8 |
| 6 | 16 |
| 7 | 34 |
| 8 | 72 |
| 9 | 154 |
| 10 | 336 |
| 11 | 738 |
| 12 | 1632 |
| 13 | 3640 |
| 14 | 8160 |
| 15 | 18384 |
| 16 | 41616 |
| 17 | 94560 |
| 18 | 215600 |
| 19 | 493122 |
| 20 | 1130976 |
| 21 | 2600388 |
| 22 | 5992560 |
| 23 | 13838306 |
| 24 | 32016576 |
| 25 | 74203112 |
| 26 | 172252080 |
| 27 | 400451282 |
| 28 | 932247360 |
| 29 | 2173035800 |
| 30 | 5071299968 |
| 31 | 11848259458 |
| 32 | 27710346528 |
| 33 | 64871460996 |