Can anyone help me with this summation problem:

5+7+9+11+13=sigma top number is 4 the index starts at 0. I'm supposed to find a function, but don't know how to solve that. Thank you.

Question

Can anyone help me with this summation problem:

5+7+9+11+13=sigma top number is 4 the index starts at 0. I'm supposed to find a function, but don't know how to solve that. Thank you.

anonymous · Answer

look like you are adding two each time

anonymous · Answer

$4\times 2+5=13$ so perhaps try 
$$\sum_0^42k+5$$

anonymous · Answer

$$\sum_{i=0}^{4}5+2i=5+7+9+11+13$$The reason it's 5 + 2i is because 5+2(0) = 5, 5+2(1)=7, and so on.

anonymous · Answer

or $i$, either way

anonymous · Answer

I see. So in order to get the equation one must look at the patter at the numbers being added then multiply by the n of the summation and add it to the first number to get the last one?