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 | 9 |
| 2 | 74 |
| 3 | 610 |
| 4 | 5020 |
| 5 | 41317 |
| 6 | 340050 |
| 7 | 2798709 |
| 8 | 23034169 |
| 9 | 189577752 |
| 10 | 1560278726 |
| 11 | 12841536934 |
| 12 | 105689495131 |
| 13 | 869854553902 |
| 14 | 7159149960981 |
| 15 | 58921836913893 |
| 16 | 484943447787706 |
| 17 | 3991222267830858 |
| 18 | 32848892512931768 |
| 19 | 270355712339865433 |
| 20 | 2225104276073281126 |
| 21 | 18313239977617203949 |