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 | 8 |
| 2 | 44 |
| 3 | 336 |
| 4 | 2166 |
| 5 | 11832 |
| 6 | 60576 |
| 7 | 292248 |
| 8 | 1334817 |
| 9 | 5840296 |
| 10 | 24637976 |
| 11 | 100684376 |
| 12 | 400255050 |
| 13 | 1553016960 |
| 14 | 5897388492 |
| 15 | 21967711160 |
| 16 | 80425346844 |
| 17 | 289868771928 |
| 18 | 1029979010972 |
| 19 | 3612517052608 |
| 20 | 12520285820362 |
| 21 | 42919328903928 |
| 22 | 145643017892472 |
| 23 | 489606988741128 |