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 | 13 |
| 3 | 22 |
| 4 | 44 |
| 5 | 90 |
| 6 | 196 |
| 7 | 406 |
| 8 | 852 |
| 9 | 1778 |
| 10 | 3740 |
| 11 | 7822 |
| 12 | 16404 |
| 13 | 34346 |
| 14 | 72004 |
| 15 | 150822 |
| 16 | 316076 |
| 17 | 662186 |
| 18 | 1387596 |
| 19 | 2907262 |
| 20 | 6091780 |
| 21 | 12763778 |
| 22 | 26744268 |
| 23 | 56036566 |
| 24 | 117413804 |
| 25 | 246015450 |
| 26 | 515476036 |
| 27 | 1080072022 |
| 28 | 2263070868 |
| 29 | 4741795442 |