PAT B 1087 how many different values

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Title:

Input Sample:

2017

Sample output:

1480

Code below (Python):

N = int(input())
lst = []
for i in range(1, N+1):
    t1 = i//2
    t2 = i//3
    t3 = i//5
    lst.append(t1+t2+t3)
print(len(list(set(lst))))