10th try!

[n m]=size(a);
z=n*m;
x=1:z
for i=x
    p{i}=i;
end
for i=x
    for k=x
        e=p{k}(end);
        h = a(e)+1;
        g = e-1;
        w = e+n;
        f = mod(g,n);        
        if w<=z & a(w)==h
            p{k} = [p{k} w];
        elseif e>n & a(e-n)==h
            p{k} = [p{k} e-n];
        elseif f<n-1 & a(e+1)==h
            p{k} = [p{k} e+1];
        elseif f & a(g)==h
            p{k} = [p{k} g];
        end
        d(k) = nnz(p{k});
    end
end
[v b]=max(d);
b = p{b}'