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 | 12 |
| 2 | 42 |
| 3 | 156 |
| 4 | 582 |
| 5 | 2172 |
| 6 | 8106 |
| 7 | 30252 |
| 8 | 112902 |
| 9 | 421356 |
| 10 | 1572522 |
| 11 | 5868732 |
| 12 | 21902406 |
| 13 | 81740892 |
| 14 | 305061162 |
| 15 | 1138503756 |
| 16 | 4248953862 |
| 17 | 15857311692 |
| 18 | 59180292906 |
| 19 | 220863859932 |
| 20 | 824275146822 |
| 21 | 3076236727356 |
| 22 | 11480671762602 |
| 23 | 42846450323052 |
| 24 | 159905129529606 |
| 25 | 596774067795372 |
| 26 | 2227191141651882 |