Number neither whose Half is Odd nor Power of Two is both Even-Times Even and Even-Times Odd

Theorem
Let $a \in \Z$ be an integer such that:
 * $(1): \quad a$ is not a power of $2$
 * $(2): \quad \dfrac a 2$ is an even integer.

Then $a$ is both even-times even and even-times odd.

Proof
As $\dfrac a 2$ is an even integer it follows that:
 * $\dfrac a 2 = 2 r$

for some $r \in \Z$.

That is:
 * $a = 2^2 r$

and so $a$ is even-times even by definition.

$a$ is not even-times odd.

Then $a$ does not have an odd divisor.

Thus in its prime decomposition there are no odd primes.

Thus $a$ is in the form:
 * $a = 2^k$

for some $k \in \Z_{>0}$.

That is, $a$ is a power of $2$.

This contradicts condition $(1)$.

From this contradiction it is deduced that $a$ is even-times odd.