offset matrix multiplication with loop

Hello,

I have two matrices A(i,j) and B(i,j) where 'i' is row and 'j' is column both of size 1486X41. I am trying to use a loop to multiply the two together such that the first term in each column of A is skipped, I.E. multiply A(2,1) with B(1,1) to give C(1,1) and then A(3,1) with B(2,1) for C(2,1) and so on. The final matrix size will be now 1485X41. I've attempted using a for loop but I struggle with thinking through the code. So far my efforts have led me to:

for i = 1:(length(A)-1)
    at = A(i+1)-A(1)
    C = B*at
end

I hope my question is clear, and I apologize in advanced for any confusion with the wording. Thank you.

Answer 1

[Jos (10584)]

% test data
A = randi(10,3,4) 
B = cumsum(ones(size(A))) 
% engine
C = A(2:end,:) .* B(1:end-1,:)  % C(i,j) = A(i+1,j) * B(i,j)

[Emilio Alverio]

This worked wonderfully. Thank you for your help!