>>10991693Suppose we have n niggers and Dylann
To choose k+1 members from Dylann and his...friends, we can either
A: pick Dylann, and k other people from the remaining n niggers (first part of LHS) or
B: put Dylann aside and choose k+1 people out of the remaining n niggers (second part of LHS)
This is all options exhausted hence we get equality
Intuition in combinatorics is much much more useful than just showing equality of formulae like in your pic
