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 | 4 |
| 2 | 9 |
| 3 | 21 |
| 4 | 51 |
| 5 | 127 |
| 6 | 324 |
| 7 | 844 |
| 8 | 2243 |
| 9 | 6073 |
| 10 | 16736 |
| 11 | 46892 |
| 12 | 133443 |
| 13 | 385277 |
| 14 | 1127352 |
| 15 | 3339464 |
| 16 | 10003395 |
| 17 | 30269129 |
| 18 | 92422160 |
| 19 | 284470820 |
| 20 | 881804563 |
| 21 | 2750412037 |
| 22 | 8625112792 |
| 23 | 27174303856 |
| 24 | 85960269683 |
| 25 | 272856760081 |
| 26 | 868664396112 |