n = 5;
nb = 2;

A = rand( n, n );
A = A + A';

L = rand( n, n );
L = L + n * eye( n );

C = tril( L ) \ A / tril( L )';

Y = zeros( n, n );

Cnew = InvLAInvLH_blk_var5( A, L, Y, nb );

tril( C ) - tril( Cnew ) + triu( A, 1 ) - triu( Cnew, 1 )
