C program to print pattern

hi guys i want to print this pattern


http://pastebin.com/mrcjWzAr

#include<stdio.h>
#include<conio.h>

void main()

{
char i,j,k,c,d;
int a,b,n;

for(a=0;a<=6;a++)
{
//for(n=1;n<=6;n++)
for(b=1;b<=2*b;b++)
{
for(c='G';c>='A';c--)
{
for(d='A';d<='G';d++)
{
printf("%c",d);
}
printf("%c",c);
}
printf(" ");
}

printf("\n");

}


getch();
}

but my program runs into infinite loop..
i find printing patterns very hard any suggestions?

> for(b=1;b<=2*b;b++)
Perhaps you should stop moving the goal-posts.
b <= 2
becomes
b <= 4 (when b is 2)
becomes
b <= 6 (when b is 3)