\begin{definition}[Definition:Sierpiński Number of the Second Kind]
A '''Sierpiński number of the second kind''' is an odd positive integer $k$ such that integers of the form $k2^n + 1$ are composite for all positive integers $n$.
That is, when $k$ is a '''Sierpiński number of the second kind''', all members of the set:
:$\left\{{k 2^n + 1}\right\}$
are composite.
\end{definition}