Question 940999
Assuming you mean digit sum of 18, there are 670 of them, which would take up a lot of space to list here, so here is my Python code:

def counter():
__count = 0
__for a in range(0,10):
____for b in range(0,10):
______for c in range(0,10):
________for d in range(0,10):
__________if a+b+c+d == 18:
____________count += 1
__print count


The generating function for F(x) # of 4-digit numbers with the sum-of-digits property (leading 0's included) is


*[tex \large F(x) = (1+x+x^2+\ldots+x^9)(1+x+x^2+\ldots+x^9)(1+x+x^2+\ldots+x^9)(1+x+x^2+\ldots+x^9)]


*[tex \large = (1+x+x^2+\ldots+x^9)^4]


*[tex \large = \left(\frac{x^{10} - 1}{x-1} \right)^4]