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 | 5 |
| 2 | 37 |
| 3 | 299 |
| 4 | 2517 |
| 5 | 21700 |
| 6 | 190051 |
| 7 | 1683218 |
| 8 | 15033173 |
| 9 | 135142796 |
| 10 | 1221246132 |
| 11 | 11083374659 |
| 12 | 100946732307 |
| 13 | 922205369324 |
| 14 | 8446802334994 |
| 15 | 77542088287444 |
| 16 | 713250450657109 |
| 17 | 6572130378649468 |
| 18 | 60652194138406780 |
| 19 | 560522209086365852 |