EN
Let [0;a₁(x),a₂(x),…] be the regular continued fraction expansion of an irrational x ∈ [0,1]. We prove mainly that, for α > 0, β ≥ 0 and for almost all x ∈ [0,1],
$lim_{n→∞} (aⁿ₁(x) + … + aⁿₙ(x))/nlogn = α/log2$ if α < 1 and β ≥ 0,
$lim_{n→∞} (aⁿ₁(x) + … + aⁿₙ(x))/nlogn = 1/log2$ if α = 1 and β < 1,
and, if α > 1 or α = 1 and β >1,
$lim inf_{n→∞} (aⁿ₁(x) + … + aⁿₙ(x))/nlogn = 1/log2$,
$lim sup_{n→∞} (aⁿ₁(x) + … + aⁿₙ(x))/nlogn = ∞$,
where $aⁿ_{i}(x) = a_{i}(x)$ if $a_{i}(x) ≤ n^{α}log^{β}n$ and $aⁿ_{i}(x) = 0$ otherwise, for all i ∈ {1,…,n}.