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 | 81 |
| 3 | 253 |
| 4 | 791 |
| 5 | 2173 |
| 6 | 5241 |
| 7 | 12567 |
| 8 | 28101 |
| 9 | 61397 |
| 10 | 131083 |
| 11 | 272789 |
| 12 | 560651 |
| 13 | 1133751 |
| 14 | 2266643 |
| 15 | 4487109 |
| 16 | 8799557 |
| 17 | 17130019 |
| 18 | 33113221 |
| 19 | 63623053 |
| 20 | 121586791 |
| 21 | 231212705 |
| 22 | 437760595 |
| 23 | 825496887 |
| 24 | 1550995293 |
| 25 | 2904417145 |
| 26 | 5422206945 |
| 27 | 10094193051 |