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For dividend a ,
divisor d , quotient q , and b = 2^mp_bits_per_limb , this remainder r is of the form a = q*d + r*b^n n represents the number of zero limbs produced by the subtractions,
that being the number of limbs produced for q . r will be in the
range 0<=r<d and can be viewed as a remainder, but one shifted up by
a factor of b^n .