Let
hURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0024379516301847&_mathId=si1.gif&_user=111111111&_pii=S0024379516301847&_rdoc=1&_issn=00243795&md5=9f566079dbc8214b66012be5973fd28d">![View the MathML source View the MathML source](/sd/grey_pxl.gif)
be strict contractions on a Hilbert space
H. The
n×n operator matrix
![View the MathML source View the MathML source](/sd/grey_pxl.gif)
is called a Hua-type operator matrix. In this note, we mainly investigate some results which are related to the Hua-type operator matrix. We firstly give some equivalent conditions for the positivity of
n×n operator matrices
![View the MathML source View the MathML source](/sd/grey_pxl.gif)
. Then the equation
min{‖H2(A1,A2)‖:‖A1‖<1,‖A2‖<1}=2 is shown. In particular, some equivalent conditions for strict contractions
A1 and
A2 such that
‖H2(A1,A2)‖=2 are obtained.