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 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 11 |
| 4 | 25 |
| 5 | 52 |
| 6 | 103 |
| 7 | 199 |
| 8 | 380 |
| 9 | 724 |
| 10 | 1382 |
| 11 | 2649 |
| 12 | 5103 |
| 13 | 9881 |
| 14 | 19224 |
| 15 | 37559 |
| 16 | 73646 |
| 17 | 144848 |
| 18 | 285623 |
| 19 | 564429 |
| 20 | 1117396 |
| 21 | 2215436 |
| 22 | 4398054 |
| 23 | 8740266 |
| 24 | 17385207 |
| 25 | 34607218 |
| 26 | 68934319 |
| 27 | 137386725 |
| 28 | 273942683 |
| 29 | 546450648 |
| 30 | 1090419638 |