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 | 4 |
| 2 | 14 |
| 3 | 52 |
| 4 | 217 |
| 5 | 1033 |
| 6 | 5604 |
| 7 | 34416 |
| 8 | 237328 |
| 9 | 1822753 |
| 10 | 15473117 |
| 11 | 144165763 |
| 12 | 1464992791 |
| 13 | 16144683412 |
| 14 | 191967912402 |
| 15 | 2451561765083 |
| 16 | 33487399558154 |
| 17 | 487448547177703 |
| 18 | 7535687673952024 |
| 19 | 123349262218035648 |