344145domain: NAppears in sequencesExpansion of Sum_{i>=1} mu(i)^2*x^i / (1 - Sum_{j>=1} mu(j)^2*x^j)^2, where mu() is the Moebius function (A008683).at n=16A281812a(0) = ... = a(3) = 1; a(n) = a(n-4) + Sum_{k=0..n-5} a(k) * a(n-k-5).at n=34A343305