h.pconstr

来自「强大的数学工具包」· PCONSTR 代码 · 共 36 行

                               * * * * * * *
                               *  pconstr  *
                               * * * * * * *

        "prime construction"
        SYNTAX: X = pconstr(z, n)

        z is an expression whose value is a positive integer. 
        n must be 0,1 or 2.

        pconstr constructs a prime X > z with the following 
        attributes:
        - if n=0: X-1 has only prime factors < M , 
                  M= min{1000,(max(rand)+1)th prime number}
        - if n=1: X-1 has one prime factor in the order of X.
        - if n=2: X-1 has two prime factors in the order of
                  sqrt(X).

        pconstr displays also the prime factorization of X-1.

        AV[0]=X-1. Afterwards the factorization of X-1 in the
        form factor - exponent in increasing order is stored
        in AV (see "?avfunc").


        Example 1: (correct)

                X = pconstr( 10^50,1 )


        Example 2: (incorrect)

                X = pconstr( 34523454,4 )

_ERR_NR_020