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 | 14 |
| 3 | 86 |
| 4 | 518 |
| 5 | 3110 |
| 6 | 18662 |
| 7 | 111974 |
| 8 | 671846 |
| 9 | 4031078 |
| 10 | 24186470 |
| 11 | 145118822 |
| 12 | 870712934 |
| 13 | 5224277606 |
| 14 | 31345665638 |
| 15 | 188073993830 |
| 16 | 1128443962982 |
| 17 | 6770663777894 |
| 18 | 40623982667366 |
| 19 | 243743896004198 |
| 20 | 1462463376025190 |