有限域中本原元实验.本原元——有限域GF(pm)中阶最大的元素，即阶为 pm-1 的元素。-Primitive element- finite field GF (pm) in the order of the largest element, that of order pm-1 elements. Collection of the finite field GF (p) [x] refers to: coefficient of 0, ..., p-1 the polynomial of the set. Collection of the finite field GF (2) [x]/(x8+x4+x3+x+1) refers to: {(0,1 polynomial coefficient)　(x8+x4+x3+x+1)}, namely: 0,1 polynomial coefficient divided by (x8+x4+x3+x+1) obtained remainder type of collection. Finite field GF (2) [x]/(x8+x4+x3+x+1) in a total of 28 = 256 elements.