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 | 1 |
| 2 | 17 |
| 3 | 23 |
| 4 | 125 |
| 5 | 280 |
| 6 | 1061 |
| 7 | 2870 |
| 8 | 9495 |
| 9 | 27507 |
| 10 | 86149 |
| 11 | 255704 |
| 12 | 782393 |
| 13 | 2341381 |
| 14 | 7090347 |
| 15 | 21271463 |
| 16 | 64109181 |
| 17 | 192439733 |
| 18 | 578665211 |
| 19 | 1736971814 |
| 20 | 5217197093 |
| 21 | 15658051930 |
| 22 | 47004010481 |
| 23 | 141050402559 |
| 24 | 423295193635 |
| 25 | 1270100996174 |