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) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 18 |
| 5 | 44 |
| 6 | 110 |
| 7 | 272 |
| 8 | 676 |
| 9 | 1676 |
| 10 | 4160 |
| 11 | 10320 |
| 12 | 25608 |
| 13 | 63536 |
| 14 | 157648 |
| 15 | 391152 |
| 16 | 970528 |
| 17 | 2408064 |
| 18 | 5974880 |
| 19 | 14824832 |
| 20 | 36783296 |
| 21 | 91266496 |
| 22 | 226449920 |
| 23 | 561866240 |
| 24 | 1394099328 |
| 25 | 3459031296 |
| 26 | 8582528768 |
| 27 | 21294921472 |
| 28 | 52836837888 |
| 29 | 131098461184 |