TypeError: 'int' object is not iterable in python (newbie)

You are summing an integer:

for w in range(len(results)+1):
    if (sum(w) != n):

w is an integer from the range(len(resultss)+1). If you wanted to sum the triples you produced in results, just loop directly over the results:

for w in results:
    if (sum(w) != n):

although it is not clear to me why you are looping over the length plus one. Python indices are 0-based, the last index is at len(results) - 1, not len(results).

You are making it harder on yourself than is needed. Python has several easier options you are missing here.

• list.append() returns None. You are replacing results with None here:

  results = results.append(sum(w))
  

  Remove the results = part altogether.

  And are you certain you want to combine the (x, y, z) triplets with the sum() results in one list?

• When using a list comprehension that does nothing but loop and copy the elements to a list ([i for i in iterable]), just use list() on the iterable:

  xarr = list(range(x + 1))
  

  Since all you do is iterate, you don't actually have to do this at all. And there is rarely a need to convert range() objects to lists, you can address individual indices directly without doing so. Just use your range() objects directly:

  xarr = range(x + 1)
  

• You can use the itertools.product() function to produce your results:

  from itertools import product
  
  results = product(range(x + 1), range(y + 1), range(z + 1))
  

  Again, no need to convert this to a list since you are going to iterate over this.

• If you wanted to add indices of the triplets, use enumerate() to produce those together with the triples so you can test the sum, then add the index to a result list:

  indices = []
  for i, w in enumerate(results):
      if (sum(w) != n):
          indices.append(i)
  

You can put everything into a one-liner after this, using a list comprehension:

from itertools import product

x = int(raw_input())
y = int(raw_input())
z = int(raw_input())
n = int(raw_input())

indices = [i for i, w in enumerate(product(range(x + 1), range(y + 1), range(z + 1)))
           if sum(w) != n]

You don't need to use range here

"range(len(results)+1)"

As results will be a list of list [[x,y,z], [x,y,z]].

Try this:

for w in results:
    if (sum(w) != n):
        results=results.append(sum(w))

Or do like this:

for w in range(len(results)+1):
    if (sum(results[w]) != n):