Compute 2²⁰¹⁷ modulo 100.
From the given table,
2²² ≡ 2⁴² ≡ 2⁶² ≡ 4 (mod 100)
and we have
2017 = 32 • 62 + 33
62 = 1 • 42 + 20
Then
2²⁰¹⁷ ≡ (2⁶²)³² • 2³³ (mod 100)
2²⁰¹⁷ ≡ 4³² • 2³³ (mod 100)
2²⁰¹⁷ ≡ (2²)³² • 2³³ (mod 100)
2²⁰¹⁷ ≡ 2⁶⁴ • 2³³ (mod 100)
2²⁰¹⁷ ≡ 2⁶² • 2²² • 2¹³ (mod 100)
2²⁰¹⁷ ≡ 4² • 2¹³ (mod 100)
2²⁰¹⁷ ≡ (2²)² • 2¹³ (mod 100)
2²⁰¹⁷ ≡ 2⁴ • 2¹³ (mod 100)
2²⁰¹⁷ ≡ 2¹⁷ (mod 100)
and from the table, we get
2²⁰¹⁷ ≡ 2¹⁷ ≡ 72 (mod 100)
