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 | 0 |
| 2 | 4 |
| 3 | 8 |
| 4 | 36 |
| 5 | 88 |
| 6 | 272 |
| 7 | 696 |
| 8 | 1900 |
| 9 | 4856 |
| 10 | 12588 |
| 11 | 31792 |
| 12 | 80288 |
| 13 | 200304 |
| 14 | 498004 |
| 15 | 1229672 |
| 16 | 3024948 |
| 17 | 7407496 |
| 18 | 18079664 |
| 19 | 43980072 |
| 20 | 106688956 |
| 21 | 258132824 |
| 22 | 623113020 |
| 23 | 1500935776 |
| 24 | 3608439104 |
| 25 | 8659683552 |
| 26 | 20747930788 |
| 27 | 49635222728 |
| 28 | 118576046148 |