A086795 a(n) is the number of terms in the expansion of (x-2y)*(x^2-2y^2)*(x^3-2y^3)*...*(x^n-2y^n).

2, 4, 7, 11, 13, 21, 28, 35, 42, 53, 65, 74, 87, 102, 117, 133, 150