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 | 41 |
| 3 | 421 |
| 4 | 3562 |
| 5 | 37309 |
| 6 | 504880 |
| 7 | 1688724 |
| 8 | 20969807 |
| 9 | 856967187 |
| 10 | 5376948073 |
| 11 | 17667973799 |
| 12 | 73247846210 |
| 13 | 7038850387534 |
| 14 | 32764157273501 |
| 15 | 384623091229702 |
| 16 | 4924836055850737 |
| 17 | 21264412149709993 |
| 18 | 583141322266592750 |
| 19 | 5592755799950501152 |
| 20 | 78206057147010955997 |