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 | 50 |
| 2 | 2501 |
| 3 | 125100 |
| 4 | 6257501 |
| 5 | 313000150 |
| 6 | 15656265001 |
| 7 | 783126250200 |
| 8 | 39171968775001 |
| 9 | 1959381565000250 |
| 10 | 98008250218787501 |
| 11 | 4902371892504375300 |
| 12 | 245216602875437552501 |
| 13 | 12265732515664382000350 |
| 14 | 613531842386094537570001 |
| 15 | 30688857851820391260500400 |