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We study linear complementary dual four circulant codes of length 
$4n$ over 
$\mathbb{F}_{q}$ when 
$q$ is an odd prime power. When 
$q^{\unicode[STIX]{x1D6FF}}+1$ is divisible by 
$n$, we obtain an exact count of linear complementary dual four circulant codes of length 
$4n$ over 
$\mathbb{F}_{q}$. For certain values of 
$n$ and 
$q$ and assuming Artin’s conjecture for primitive roots, we show that the relative distance of these codes satisfies a modified Gilbert–Varshamov bound.
In this short note, we give a proof, conditional on the generalised Riemann hypothesis, that there exist numbers 
$x$ which are normal with respect to the continued fraction expansion but not to any base-
$b$ expansion. This partially answers a question of Bugeaud.
