MathDB
Find the matrix M with the properties

Source: IMO LongList 1979 - P7

May 29, 2011
linear algebramatrixlinear algebra unsolved

Problem Statement

M=(ai,j), i,j=1,2,3,4M = (a_{i,j} ), \ i, j = 1, 2, 3, 4, is a square matrix of order four. Given that:
[*] (i) for each i=1,2,3,4i = 1, 2, 3,4 and for each k=5,6,7k = 5, 6, 7, ai,k=ai,k4;a_{i,k} = a_{i,k-4};Pi=a1,i+a2,i+1+a3,i+2+a4,i+3;P_i = a_{1,}i + a_{2,i+1} + a_{3,i+2} + a_{4,i+3};Si=a4,i+a3,i+1+a2,i+2+a1,i+3;S_i = a_{4,i }+ a_{3,i+1} + a_{2,i+2} + a_{1,i+3};Li=ai,1+ai,2+ai,3+ai,4;L_i = a_{i,1} + a_{i,2} + a_{i,3} + a_{i,4};Ci=a1,i+a2,i+a3,i+a4,i,C_i = a_{1,i} + a_{2,i} + a_{3,i} + a_{4,i},
* for each i,j=1,2,3,4i, j = 1, 2, 3, 4, Pi=Pj,Si=Sj,Li=Lj,Ci=CjP_i = P_j , S_i = S_j , L_i = L_j , C_i = C_j, and * a1,1=0,a1,2=7,a2,1=11,a2,3=2a_{1,1} = 0, a_{1,2} = 7, a_{2,1} = 11, a_{2,3} = 2, and a3,3=15a_{3,3} = 15.
find the matrix M.