128161domain: NAppears in sequencesNumber of (w,x,y,z) with all terms in {1,...,n} and w<2x+y+z.at n=19A212145a(n) is the integer w such that (L(2*n)^2, -L(2*n-1)^2, -w) is a primitive solution to the Diophantine equation 2*x^3 + 2*y^3 + z^3 = 125, where L(n) is the n-th Lucas number (A000032).at n=6A354336