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 | 12 |
| 2 | 60 |
| 3 | 204 |
| 4 | 636 |
| 5 | 1932 |
| 6 | 5820 |
| 7 | 17484 |
| 8 | 52476 |
| 9 | 157452 |
| 10 | 472380 |
| 11 | 1417164 |
| 12 | 4251516 |
| 13 | 12754572 |
| 14 | 38263740 |
| 15 | 114791244 |
| 16 | 344373756 |
| 17 | 1033121292 |
| 18 | 3099363900 |
| 19 | 9298091724 |
| 20 | 27894275196 |
| 21 | 83682825612 |
| 22 | 251048476860 |
| 23 | 753145430604 |
| 24 | 2259436291836 |
| 25 | 6778308875532 |