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 | 1 |
| 1 | 127 |
| 2 | 1665 |
| 3 | 16255 |
| 4 | 141441 |
| 5 | 1163135 |
| 6 | 9273473 |
| 7 | 72613759 |
| 8 | 562430081 |
| 9 | 4327407487 |
| 10 | 33161347201 |
| 11 | 253517365119 |
| 12 | 1935665528961 |
| 13 | 14771256557439 |
| 14 | 112715410440321 |
| 15 | 860346088685439 |
| 16 | 6570305359184001 |
| 17 | 50209563856600959 |
| 18 | 383989436028813441 |