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 | 5 |
| 2 | 11 |
| 3 | 27 |
| 4 | 85 |
| 5 | 359 |
| 6 | 1953 |
| 7 | 12907 |
| 8 | 99461 |
| 9 | 871455 |
| 10 | 8538169 |
| 11 | 92409683 |
| 12 | 1094367597 |
| 13 | 14071365511 |
| 14 | 195177925025 |
| 15 | 2904454929339 |
| 16 | 46151637341653 |
| 17 | 779850886057967 |
| 18 | 13962610118134281 |
| 19 | 264033196462146595 |
| 20 | 5258262698750606909 |
| 21 | 110001474536281307223 |