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 | 1 |
| 3 | 3 |
| 4 | 7 |
| 5 | 15 |
| 6 | 35 |
| 7 | 83 |
| 8 | 197 |
| 9 | 473 |
| 10 | 1145 |
| 11 | 2787 |
| 12 | 6819 |
| 13 | 16759 |
| 14 | 41345 |
| 15 | 102341 |
| 16 | 254075 |
| 17 | 632437 |
| 18 | 1577967 |
| 19 | 3945517 |
| 20 | 9884379 |
| 21 | 24806201 |
| 22 | 62355121 |
| 23 | 156974319 |
| 24 | 395712759 |
| 25 | 998809135 |
| 26 | 2524043569 |
| 27 | 6385400005 |
| 28 | 16170553755 |
| 29 | 40990092629 |
| 30 | 103997889735 |