MathDB
Summation, Ceiling, and Floor Functions

Source: AIME I 2007 #7

March 15, 2007
functionceiling functionlogarithmsfloor functioncalculusintegrationLaTeX

Problem Statement

Let N=k=11000k(log2klog2k).N= \sum_{k=1}^{1000}k(\lceil \log_{\sqrt{2}}k\rceil-\lfloor \log_{\sqrt{2}}k \rfloor). Find the remainder when N is divided by 1000. (Here x\lfloor x \rfloor denotes the greatest integer that is less than or equal to x, and x\lceil x \rceil denotes the least integer that is greater than or equal to x.)