Integers with all prime factors congruent to one modulo four

A positive integer in this set has no prime factor equal to two or congruent to three modulo four. Its prime factors all lie in the residue class one modulo four. For example $5\cdot 13=65$ belongs, while $3^2=9$ does not, even though $9$ itself is congruent to one modulo four. A half-dimensional interval sieve bounds the count in an interval of length $z$ by $O(z/\sqrt{\log z})$.