Respuesta :

if its this
[tex]\sum^{4}_{k=13} k-1[/tex]

well start with the first term
13-1
add the 2nd term
14-1
add the 3rd term
15-1
andd the 4th term
16-1

since the summation only goes to 4, we stop here

13+14+15+16-4*1
would be the answer to your summation