why doesn't this code iterate through all the n in range?

Question

N = int (input())
for n in range (N+1):
n += n
print (n)

my thought is that it takes the input and let's say it is 5 and goes for all in range 6 so 0 - 5 and goes through them:
0 += 0
0 += 1
1 += 2
3 += 3
6 += 4
10 += 5
leaving n = 15 at the end but it doesn't do that

Answer 1

You need a sum variable

N = int (input())
sumVar = 0
for n in range (N+1):
sumVar += n
print (sumVar)

Shorter solution

N = int(input())
print (sum(range(1,N+1)))

Answer 2

thank you

Answer 3

What's happening is:

1st iteration
n = 0 (for n = 0..5)
n = 0 + 0 (n+=0)

2nd
n = 1
n = 1 + 1

3rd
n = 2
n = 2 + 2

.
.
.

6th
n = 5
n = 5 + 5