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 | 0 |
| 1 | 6 |
| 2 | 42 |
| 3 | 342 |
| 4 | 2730 |
| 5 | 21846 |
| 6 | 174762 |
| 7 | 1398102 |
| 8 | 11184810 |
| 9 | 89478486 |
| 10 | 715827882 |
| 11 | 5726623062 |
| 12 | 45812984490 |
| 13 | 366503875926 |
| 14 | 2932031007402 |
| 15 | 23456248059222 |
| 16 | 187649984473770 |
| 17 | 1501199875790166 |
| 18 | 12009599006321322 |
| 19 | 96076792050570582 |
| 20 | 768614336404564650 |