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 | 19 |
| 4 | 39 |
| 5 | 79 |
| 6 | 160 |
| 7 | 322 |
| 8 | 645 |
| 9 | 1292 |
| 10 | 2585 |
| 11 | 5171 |
| 12 | 10344 |
| 13 | 20689 |
| 14 | 41379 |
| 15 | 82759 |
| 16 | 165520 |
| 17 | 331043 |
| 18 | 662087 |
| 19 | 1324175 |
| 20 | 2648352 |
| 21 | 5296705 |
| 22 | 10593412 |
| 23 | 21186825 |
| 24 | 42373651 |
| 25 | 84747303 |
| 26 | 169494607 |
| 27 | 338989215 |
| 28 | 677978433 |
| 29 | 1355956867 |
| 30 | 2711913735 |
| 31 | 5423827471 |
| 32 | 10847654946 |
| 33 | 21695309894 |
| 34 | 43390619790 |
| 35 | 86781239584 |
| 36 | 173562479171 |
| 37 | 347124958343 |