Kento Kimura, Atsuki Takahashi, Tetsuya Araki, Kazuyuki Amano
Mar 15, 2021
Let $f(n)$ be the maximum number of steps of Topswops on $n$ cards. In this
note, we report our computational experiments to determine the values of
$f(18)$ and $f(19)$. By applying an algorithm developed by Knuth in a parallel
fashion, we conclude that $f(18)=191$ and $f(19)=221$.