MathDB
Sum with floor function and square roots

Source: Czech and Slovak Olympiad 1973, National Round, Problem 4

July 16, 2024
algebrafloor functionSumsum of rootsfunction

Problem Statement

For any integer n2n\ge2 evaluate the sum k=1n21k.\sum_{k=1}^{n^2-1}\bigl\lfloor\sqrt k\bigr\rfloor.