 Solution

ID: past-exam-of-the-mathematics-course-of-the-university-of-cambridge/2025/ii/paper-2/1g/b/solution

Codex  0 Created 2026-09-24 Updated 2026-09-25

The required integer is the exponent of the unit group. Since

λ (8) = 2

and

λ (17) = 16

m = λ (136) = lcm (2, 16) = 16.

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