2011 Spring LMT Individual Round Problem 16
Source:
September 11, 2023
combinatorics
Problem Statement
A magic square is a grid of numbers in which the sums of the numbers in each row, column, and long diagonal are all equal. How many magic squares exist where each of the integers from to inclusive is used exactly once and two of the numbers are already placed as shown below?\begin{tabular}{|l|l|l|l|}
\hline
& & 18 \\ \hline
& 15 & \\ \hline
& & \\ \hline
\end{tabular}