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) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 15 |
| 5 | 31 |
| 6 | 63 |
| 7 | 127 |
| 8 | 255 |
| 9 | 511 |
| 10 | 1024 |
| 11 | 2050 |
| 12 | 4102 |
| 13 | 8206 |
| 14 | 16414 |
| 15 | 32830 |
| 16 | 65662 |
| 17 | 131326 |
| 18 | 262654 |
| 19 | 525310 |
| 20 | 1050622 |
| 21 | 2101246 |
| 22 | 4202494 |
| 23 | 8404990 |
| 24 | 16809982 |
| 25 | 33619966 |
| 26 | 67239934 |
| 27 | 134479870 |
| 28 | 268959742 |
| 29 | 537919486 |
| 30 | 1075838974 |
| 31 | 2151677950 |
| 32 | 4303355902 |
| 33 | 8606711806 |