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 | 3 |
| 2 | 6 |
| 3 | 13 |
| 4 | 27 |
| 5 | 55 |
| 6 | 110 |
| 7 | 220 |
| 8 | 441 |
| 9 | 883 |
| 10 | 1766 |
| 11 | 3532 |
| 12 | 7064 |
| 13 | 14129 |
| 14 | 28258 |
| 15 | 56517 |
| 16 | 113035 |
| 17 | 226070 |
| 18 | 452140 |
| 19 | 904281 |
| 20 | 1808562 |
| 21 | 3617124 |
| 22 | 7234249 |
| 23 | 14468499 |
| 24 | 28936999 |
| 25 | 57873998 |
| 26 | 115747997 |
| 27 | 231495994 |
| 28 | 462991989 |
| 29 | 925983979 |
| 30 | 1851967959 |
| 31 | 3703935918 |