You don't really need a picture. It would suffice to have your discussion relate to some examples of sequences. I was thinking something like this: http://wordaligned.org/articles/nextpermutation
By the way, not all coders have access to reverse() method. Here is my Java implementation, which you are free to use:
//elements in a have to be sorted in ascending order
//changes the elements to achieve the next permutation
//returns false if there are no more permutations
public static boolean nextPermutation(int[] a)
{
int N=a.length;
int i=N2;
for (; i>=0; i)
if (a[i]<a[i+1])
break;
if (i<0) return false;
for (int j=N1; j>=i; j)
{
if (a[j]>a[i])
{
int temp=a[i];
a[i]=a[j];
a[j]=temp;
break;
}
}
for (int j=i+1; j<(N+i+1)/2; j++) //reverse from a[i+1] to a[N1]
{
int temp=a[j];
a[j]=a[N+ij];
a[N+ij]=temp;
}
return true;
}
