function h = etaijmin(P,m,n,i,j)
h = 0;
dims = repmat([m],[1 i]);
for xi = 1:m^i
  X = ind2coord(xi,dims);
  hX = mxetaijX(P,m,n,i,j,X);  % might as well do it fast!
  h = min(h,hX);
end
return