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) |
|---|---|
| 1 | 2 |
| 2 | 7 |
| 3 | 30 |
| 4 | 131 |
| 5 | 538 |
| 6 | 2153 |
| 7 | 8441 |
| 8 | 32484 |
| 9 | 123292 |
| 10 | 462673 |
| 11 | 1719899 |
| 12 | 6343170 |
| 13 | 23237876 |
| 14 | 84641287 |
| 15 | 306758202 |
| 16 | 1106900323 |
| 17 | 3978716442 |
| 18 | 14252356483 |
| 19 | 50897604269 |
| 20 | 181263039820 |
| 21 | 643928439234 |
| 22 | 2282348057593 |
| 23 | 8072881497390 |