Join the USAMO Guide Discord Server. Regular updates are posted there!

Let me Join!
Dismiss

Harvard-MIT Mathematics Tournament #0iy6

Harvard-MIT Mathematics TournamentHard

From module Generating Functions (Intro)

Community difficultyNo ratings yetBe the first to rate this problem.
Understand the scale
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.
Recurrence relationsGenerating functionsSums and products

Problem

Problem:

Let FnF_{n} be the Fibonacci sequence, that is, F0=0F_{0}=0, F1=1F_{1}=1, and Fn+2=Fn+1+FnF_{n+2}=F_{n+1}+F_{n}. Compute ∑n=0∞Fn/10n\sum_{n=0}^{\infty} F_{n} / 10^{n}.

← Back to all problems