hi,
Its regarding maximum period LSFR's (Linear feed back shift registers) used for generating pseudo random numbers. A tap sequence for an LFSR is the xor of certain bits in the register. For eg: I choose a primitive polynomail mod 2 x^32+x^7+x^5+x^3+x^2+x+1 is a primitive polynomial mod 2(chosen from a table) It says for an LSFR to be a maximum period LSFR, the polynomial from a tap sequence plus constant one must be a primitive polynomail mod 2 so polynomail from a top sequence+1= x^32+x^7+x^5+x^3+x^2+x+1 (as chosen earlier) How ever what is the polynomial formed the tap sequence & how is it found,I dont understand. It further says the degree of the polynomail is the length of the shift register. Here 32 is the degree,hence is a 32 bit shift register. It says a primitive polynomial of degree n is irreducable polynomial that divides (x^2)^(n-1) +1 but not (x^d)+1 for any d that divides (2^n-1) Now what is the polynomial of degree n? I thought I already had one with degree 32. which is the primitive polynomial of degree n that divides (x^2)^(n-1) +1 but not (x^d)+1 for any d that divides (2^n-1) and where did it come from? Regards Data. __________________________________________________ Do You Yahoo!? LAUNCH - Your Yahoo! Music Experience http://launch.yahoo.com