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 | 4 |
| 2 | 26 |
| 3 | 190 |
| 4 | 1462 |
| 5 | 11584 |
| 6 | 93536 |
| 7 | 765314 |
| 8 | 6323270 |
| 9 | 52638760 |
| 10 | 440815036 |
| 11 | 3709445084 |
| 12 | 31340292076 |
| 13 | 265683004240 |
| 14 | 2258793820988 |
| 15 | 19251776923210 |
| 16 | 164440378882630 |
| 17 | 1407266585304760 |
| 18 | 12063701803046300 |
| 19 | 103571977632247076 |