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 | 6 |
| 2 | 26 |
| 3 | 100 |
| 4 | 364 |
| 5 | 1288 |
| 6 | 4488 |
| 7 | 15504 |
| 8 | 53296 |
| 9 | 182688 |
| 10 | 625184 |
| 11 | 2137408 |
| 12 | 7303360 |
| 13 | 24946816 |
| 14 | 85196928 |
| 15 | 290926848 |
| 16 | 993379072 |
| 17 | 3391793664 |
| 18 | 11580678656 |
| 19 | 39539651584 |
| 20 | 134998297600 |
| 21 | 460915984384 |
| 22 | 1573671536640 |
| 23 | 5372862566400 |
| 24 | 18344123969536 |
| 25 | 62630804299776 |