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ChallengeSuperchallengeAdvanced Number Theory

Advanced Number Theory · Superchallenge problem

A sequence satisfies a0=3a_0=3, a1=7a_1=7, and an+1=4an−3an−1a_{n+1}=4a_n-3a_{n-1} for n≥1n\ge1. Find the remainder when a2025a_{2025} is divided by 100100.