Question 1003331
<pre>
First we figure out the pattern:

-4 + -1 + 8 + 23 + 44 + 71 + 104
         
 start with -4  
  -4 +  3 = -1
  -1 +  9 =  8
   8 + 15 = 23
  23 + 21 = 44
  44 + 27 = 71
  71 + 33 = 104

We are adding an odd multiple of 3 each time.
So we could write it this way:

   start with -4  
  -4 +  3*1 = -1
  -1 +  3*3 =  8
   8 +  3*5 = 23
  23 +  3*7 = 44
  44 +  3*9 = 71
  71 + 3*11 = 104

We start with this

-4 + -1 + 8 + 23 + 44 + 71 + 104

and go through a bunch of substitutions using the above list

-4 + -1 + 8 + 23 + 44 + 71 + 1*(71 + 3*11)

-4 + -1 + 8 + 23 + 44 + 71 + 71 + 1*3*11

-4 + -1 + 8 + 23 + 44 + 2*71 + 1*3*11

-4 + -1 + 8 + 23 + 44 + 2*(44 +  3*9) + 1*3*11

-4 + -1 + 8 + 23 + 44 + 2*44 +  2*3*9 + 1*3*11

-4 + -1 + 8 + 23 + 3*44 +  2*3*9 + 3*11

-4 + -1 + 8 + 23 + 3*(23 +  3*7) +  2*3*9 + 1*3*11

-4 + -1 + 8 + 23 + 3*23 +  3*3*7 +  2*3*9 + 1*3*11

-4 + -1 + 8 + 4*23 +  3*3*7 +  2*3*9 + 3*11

-4 + -1 + 8 + 4*(8 +  3*5) +  3*3*7 +  2*3*9 + 1*3*11

-4 + -1 + 8 + 4*8 +  4*3*5 +  3*3*7 +  2*3*9 + 1*3*11

-4 + -1 + 5*8 +  4*3*5 +  3*3*7 +  2*3*9 + 1*3*11

-4 + -1 + 5*(-1 +  3*3) +  4*3*5 +  3*3*7 +  2*3*9 + 1*3*11

-4 + -1 + 5*(-1) +  5*3*3 +  4*3*5 +  3*3*7 +  2*3*9 + 1*3*11

-4 + 6*(-1) +  5*3*3 +  4*3*5 +  3*3*7 +  2*3*9 + 1*3*11

-4 + 6*(-4 +  3*1) +  5*3*3 +  4*3*5 +  3*3*7 +  2*3*9 + 1*3*11

-4 + 6*(-4) +  6*3*1 +  5*3*3 +  4*3*5 +  3*3*7 +  2*3*9 + 1*3*11

7*(-4) +  6*3*1 +  5*3*3 +  4*3*5 +  3*3*7 +  2*3*9 + 1*3*11

-28 + 3*(6*1 +  5*3 +  4*5 +  3*7 +  2*9 + 1*11)

Using the formula for the nth term of an arithmetic sequence 

                        {{{a[n]=a[1]+(n-1)d}}}

The sequence 6,5,4,3,2,1 has kth term 6+(k-1)(-1) = 6-k+1 = 7-k

The sequence 1,3,5,7,9,11 has kth term 1+(k-1)(2) = 1+2k-2 = 2k-1

In summation form is

{{{-28}}}{{{""+""}}}{{{3*sum(((7-k)^""(2k-1)),matrix(1,2,"",k=1),matrix(1,3,"","",6))}}}


Edwin</pre>