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 | 13 |
| 2 | 76 |
| 3 | 413 |
| 4 | 2638 |
| 5 | 15460 |
| 6 | 92817 |
| 7 | 557439 |
| 8 | 3332685 |
| 9 | 19979228 |
| 10 | 119669673 |
| 11 | 716821452 |
| 12 | 4294298464 |
| 13 | 25723862625 |
| 14 | 154096718455 |
| 15 | 923100717695 |
| 16 | 5529722705330 |
| 17 | 33125219903271 |
| 18 | 198432924637760 |
| 19 | 1188690440868116 |
| 20 | 7120718914489889 |