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 | 3 |
| 2 | 7 |
| 3 | 14 |
| 4 | 40 |
| 5 | 108 |
| 6 | 362 |
| 7 | 1182 |
| 8 | 4150 |
| 9 | 14602 |
| 10 | 52588 |
| 11 | 190746 |
| 12 | 699600 |
| 13 | 2581428 |
| 14 | 9588742 |
| 15 | 35792568 |
| 16 | 134223910 |
| 17 | 505294128 |
| 18 | 1908896442 |
| 19 | 7233642930 |
| 20 | 27487869472 |
| 21 | 104715443852 |
| 22 | 399822696082 |
| 23 | 1529755490574 |
| 24 | 5864063066500 |
| 25 | 22517998808028 |
| 26 | 86607689013412 |
| 27 | 333599974893066 |