1 997 : 4 = 499 rest 1
1 997 = 4 × 499 + 1
Uc(3^1997) = Uc(3^1) = 3
Uc(4^1997) = Uc(4^1) = 4
Uc(5^1997) = 5 (5 la orice putere, are ultima cifra 5)
Uc(6^1997) = 6 (6 la orice putere, are ultima cifra 6)
Uc(7^1997) = Uc(7^1) = 7
Uc(8^1997) = Uc(8^1) = 8
Uc(9^1997) = 9 (9 la o putere impara, are ultima cifra 9 si 9 la o putere para, are ultima cifra 1)