Goldbach Conjecture

[DrD]

Here's a short program to display both the number of Goldbach partitions, and a list containing them:

For additional "fun" points, can you graph the number of resulting partitions vs. an even number (greater than 4) that produces a composition of twin prime summands?

Code:

 
//============================================
//  Goldbach Conjecture, June 7,1742         =
//                                           =
//  Lists the number of Goldbach twin-prime  =
//  summand pairs,                           =
//  Enter an even number greater than 4      =
//  Displays Number of, and List of          =
//           Goldbach Partitions.            =
//                                           =
// ===========================================

EXPORT Gold(n)
BEGIN
local a:=0, i ;    
    L1:={};
    print();
    for i from 3 to n  do 
        if isprime(i) and isprime(n-i) then  
            L1:=concat(L1,{{i,(n-i)}}); //  Full Goldbach Composition
            a:= a+1 ;  //  Total number of Goldbach elements
        end; 
    end; 
    print("Goldbach Partitions " + a/2);  //  Number of distinct Goldbach partitions
    print(L1({1,size(L1)/2})); //  Goldbach partition listing
END;