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 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 12 |
| 5 | 30 |
| 6 | 75 |
| 7 | 188 |
| 8 | 472 |
| 9 | 1186 |
| 10 | 2981 |
| 11 | 7494 |
| 12 | 18842 |
| 13 | 47376 |
| 14 | 119126 |
| 15 | 299545 |
| 16 | 753220 |
| 17 | 1894018 |
| 18 | 4762640 |
| 19 | 11976010 |
| 20 | 30114592 |
| 21 | 75725485 |
| 22 | 190417684 |
| 23 | 478820320 |
| 24 | 1204031670 |
| 25 | 3027633300 |
| 26 | 7613224740 |
| 27 | 19144059492 |
| 28 | 48139261637 |
| 29 | 121050006438 |