129029domain: NAppears in sequencesOne less than six times product of first n primes of form 6k-1.at n=3A057131Counts where both the odd composites (starting from 1) 1 mod 4 and 3 mod 4 are equal.at n=25A093182G.f. satisfies A(x) = 1/(1 - 2*x) - x*A(x)^3.at n=21A364641