Swedish number plates

"""
Swedish car plates: ABC123
where 123 must be either
1 + 2 = 3 // right
1 - 2 = 3 // wrong
1 * 2 = 3 // wrong
1 / 2 = 3 // wrong
=> Is a valid plate,
cuz one arithmetic operation works
and the third number can be created using one of these
arithmetic operations in the correct order of the numbers.
"""


valid_numbers = [int(i) for i in range(10)]
alphabet = ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z']

num_letter_combinations = len(alphabet) ** 3

result = set()
num_number_combinations = 0

for i in range(10):
    for j in range(10):
        if i + j in valid_numbers:
            r = i * 100 + j * 10 + (i + j)
            result.add(r)
            print(i, "+", j, "=", i + j, ";%03d" % r)

        if i - j in valid_numbers:
            r = i * 100 + j * 10 + (i - j)
            result.add(r)
            print(i, "-", j, "=", i - j, ";%03d" % r)

        if j > 0 and i % j == 0 and i / j in valid_numbers:
            r = i * 100 + j * 10 + (i / j)
            result.add(r)
            print(i, "/", j, "=", int(i / j), ";%03d" % r)

        if i * j in valid_numbers:
            r = i * 100 + j * 10 + (i * j)
            result.add(r)
            print(i, "*", j, "=", i * j, ";%03d" % r)

result = list(result)
result.sort()
num_number_combinations = len(result)


print("Letter Combinations:", num_letter_combinations)
print("Number Combinations:", num_number_combinations)
print("Total Combinations:", num_letter_combinations * num_number_combinations)