MathDB
Arithmetic Sequence

Source: 1999 National High School Mathematics League, Exam One, Problem 15

March 10, 2020
arithmetic sequence

Problem Statement

Given positive integer nn and positive number MM. For all arithmetic squence a1,a2,,a_1,a_2,\cdots, that a12+an+12Ma_1^2+a_{n+1}^2\leq M, find the maximum value of S=an+1+an+2+,a2n+1S=a_{n+1}+a_{n+2}+\cdots,a_{2n+1}.