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 | 9 |
| 3 | 21 |
| 4 | 46 |
| 5 | 99 |
| 6 | 209 |
| 7 | 436 |
| 8 | 901 |
| 9 | 1849 |
| 10 | 3774 |
| 11 | 7671 |
| 12 | 15541 |
| 13 | 31404 |
| 14 | 63329 |
| 15 | 127501 |
| 16 | 256366 |
| 17 | 514939 |
| 18 | 1033449 |
| 19 | 2072676 |
| 20 | 4154701 |
| 21 | 8324529 |
| 22 | 16673534 |
| 23 | 33386671 |
| 24 | 66837421 |
| 25 | 133778524 |
| 26 | 267724809 |
| 27 | 535721061 |
| 28 | 1071881326 |
| 29 | 2144473299 |
| 30 | 4290096449 |
| 31 | 8582053396 |
| 32 | 17167117141 |