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 | 1 |
| 2 | 4 |
| 3 | 26 |
| 4 | 122 |
| 5 | 2102 |
| 6 | 23102 |
| 7 | 450452 |
| 8 | 9189182 |
| 9 | 193993802 |
| 10 | 3792578792 |
| 11 | 116454478142 |
| 12 | 5415133233512 |
| 13 | 252305096583542 |
| 14 | 11561510014033982 |
| 15 | 562558737261811292 |
| 16 | 31359378912013061912 |
| 17 | 1792403716245452460152 |
| 18 | 98060777857864844592572 |
| 19 | 4456958491657464897364262 |