Abstract. We prove that an operator valued positive definite function defined on an interval of ${\msbm Z}^2$ with the lexicographic order can be extended to a positive definite function on the whole discrete plane.
AMS Subject Classification
(1991): 43A35, 47D03
Keyword(s):
operator valued positive definite functions,
semigroup of operators,
lexicographic order
Received April 29, 1999, and in revised form November 8, 1999. (Registered under 2756/2009.)
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