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 | 2 |
| 2 | 7 |
| 3 | 20 |
| 4 | 51 |
| 5 | 122 |
| 6 | 281 |
| 7 | 632 |
| 8 | 1399 |
| 9 | 3062 |
| 10 | 6645 |
| 11 | 14324 |
| 12 | 30707 |
| 13 | 65522 |
| 14 | 139249 |
| 15 | 294896 |
| 16 | 622575 |
| 17 | 1310702 |
| 18 | 2752493 |
| 19 | 5767148 |
| 20 | 12058603 |
| 21 | 25165802 |
| 22 | 52428777 |
| 23 | 109051880 |
| 24 | 226492391 |
| 25 | 469762022 |
| 26 | 973078501 |
| 27 | 2013265892 |
| 28 | 4160749539 |