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 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 24 |
| 5 | 78 |
| 6 | 268 |
| 7 | 956 |
| 8 | 3496 |
| 9 | 12998 |
| 10 | 48876 |
| 11 | 185268 |
| 12 | 706456 |
| 13 | 2706204 |
| 14 | 10404696 |
| 15 | 40124792 |
| 16 | 155133904 |
| 17 | 601113158 |
| 18 | 2333671756 |
| 19 | 9075266372 |
| 20 | 35345525944 |
| 21 | 137847053108 |
| 22 | 538258923016 |
| 23 | 2104101060872 |
| 24 | 8233434921904 |
| 25 | 32247612071708 |
| 26 | 126410623214968 |
| 27 | 495918566502536 |