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 | 7 |
| 2 | 37 |
| 3 | 187 |
| 4 | 913 |
| 5 | 4447 |
| 6 | 21373 |
| 7 | 102763 |
| 8 | 490729 |
| 9 | 2344615 |
| 10 | 11154493 |
| 11 | 53088643 |
| 12 | 251931385 |
| 13 | 1195905895 |
| 14 | 5664817573 |
| 15 | 26839963627 |
| 16 | 126961839601 |
| 17 | 600692091703 |
| 18 | 2838415775797 |
| 19 | 13414448995411 |
| 20 | 63331776834145 |
| 21 | 299041867336303 |