For real number x, use [x] to represent the largest integer not exceeding x, such as [0.32] = 0, [5.68] = 5. If n is a positive integer, an = [N4], and Sn is the sum of the first n terms of the sequence {an}, then S8=______ 、S4n=______ ．

For real number x, use [x] to represent the largest integer not exceeding x, such as [0.32] = 0, [5.68] = 5. If n is a positive integer, an = [N4], and Sn is the sum of the first n terms of the sequence {an}, then S8=______ 、S4n=______ ．

According to the meaning of the title, ∵ n is a positive integer, an = [N4], ∵ a (4K + 1) = [4K + 14] = k, a (4K + 2) = [4K + 24] = k, a (4K + 3) = [4K + 34] = k, a4k = [4k4] = k, ∵ S8 = a1 + A2 + +a8=0+1+2+3=6，S4n=a1+a2+… +a4n=4（0+1+2+3+… +N-1) + n = 4 × n (n − 1) 2 + n = 2n2-n, so