Source code in the pl/i programming language

antiprimes: procedure options(main);

    /* count the factors of a number */
    countFactors: procedure(n) returns(fixed);
        declare (n, i, count) fixed;
        if n<2 then return(1);
        count = 1;
        do i=1 to n/2;
            if mod(n,i) = 0 then count = count + 1;
        end;
        return(count);
    end countFactors;
    
    declare maxFactors fixed static init (0);
    declare seen fixed static init (0);
    declare n fixed;
    declare factors fixed;
    
    do n=1 repeat(n+1) while(seen < 20);
        factors = countFactors(n);
        if factors > maxFactors then do;
            put edit(n) (F(5));
            maxFactors = factors;
            seen = seen + 1;
            if mod(seen,15) = 0 then put skip;
        end;
    end;
end antiprimes;