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February 2017 #0k0c

February 2017Hard

From module Strong Number Theory

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Scale 0.5: Easiest math competition problems, often solvable even for early middle school students without experience. 1: Problems strictly for beginners, often at a moderate middle school level. 1.5: Problems for stronger beginner students, on the level of the middling problems in most middle school contests. 2: For motivated beginners, harder questions from the previous categories. 2.5: More advanced beginner problems, hardest questions from previous categories. 3: Early intermediate problems that require more creative thinking. 3.5: Tougher early intermediate problems that consistently stretch into higher-level creative thinking or conceptual knowledge. 4: Intermediate-level problems. 4.5: Upper intermediate problems approaching the upper bound for non-invitational sprint math competitions. 5: More difficult AIME problems or simple proof-based Olympiad-style problems. 6: High-level AIME-styled questions or introductory Olympiad-level questions. 7: Tougher Olympiad-level questions, may require more technical knowledge. 8: High-level Olympiad-level questions. 9: Expert Olympiad-level questions. 9.5: The hardest problems appearing on Olympiads which the strongest students could reasonably solve. 10: Historically notorious problems, generally unsuitable for even very hard competitions because they are exceedingly tedious, long, and difficult.
Polynomials mod pQuadratic residuesRecurrence relationsField Theory

Problem

Problem:

The Fibonacci sequence is defined as follows: F0=0F_{0}=0, F1=1F_{1}=1, and Fn=Fn−1+Fn−2F_{n}=F_{n-1}+F_{n-2} for all integers n≥2n \geq 2. Find the smallest positive integer mm such that Fm≡0(mod127)F_{m} \equiv 0 \pmod{127} and Fm+1≡1(mod127)F_{m+1} \equiv 1 \pmod{127}.

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