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 | 0 |
| 2 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 22 |
| 6 | 54 |
| 7 | 134 |
| 8 | 334 |
| 9 | 822 |
| 10 | 2014 |
| 11 | 4934 |
| 12 | 12110 |
| 13 | 29750 |
| 14 | 73086 |
| 15 | 179494 |
| 16 | 440750 |
| 17 | 1082262 |
| 18 | 2657630 |
| 19 | 6526342 |
| 20 | 16026766 |
| 21 | 39356662 |
| 22 | 96646974 |
| 23 | 237332966 |
| 24 | 582812014 |
| 25 | 1431196758 |
| 26 | 3514554142 |
| 27 | 8630600774 |
| 28 | 21193942094 |
| 29 | 52045411766 |
| 30 | 127806567678 |