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 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 23 |
| 5 | 63 |
| 6 | 137 |
| 7 | 329 |
| 8 | 738 |
| 9 | 1618 |
| 10 | 3562 |
| 11 | 7578 |
| 12 | 16116 |
| 13 | 33540 |
| 14 | 69384 |
| 15 | 141608 |
| 16 | 286493 |
| 17 | 574173 |
| 18 | 1140355 |
| 19 | 2247835 |
| 20 | 4394415 |
| 21 | 8532983 |
| 22 | 16450061 |
| 23 | 31513869 |
| 24 | 59991541 |
| 25 | 113536117 |
| 26 | 213659967 |
| 27 | 399910311 |
| 28 | 744672519 |
| 29 | 1379758479 |
| 30 | 2544367633 |