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 | 7 |
| 2 | 49 |
| 3 | 316 |
| 4 | 2032 |
| 5 | 13045 |
| 6 | 83737 |
| 7 | 537496 |
| 8 | 3450100 |
| 9 | 22145617 |
| 10 | 142149013 |
| 11 | 912430732 |
| 12 | 5856740200 |
| 13 | 37593435373 |
| 14 | 241305971377 |
| 15 | 1548902653984 |
| 16 | 9942146967292 |
| 17 | 63816977822953 |
| 18 | 409630502531629 |
| 19 | 2629349654724052 |
| 20 | 16877355480293296 |