A Nonstandard Ideal of a Radical Banach Algebra of Power Series
نویسندگان
چکیده
and, of course, the zero ideal. Such ideals are referred to as standard ideals. Any other closed ideals are denoted nonstandard ideals. It has been an open question for some time whether there exists any algebra weight {w(n)} such that ^(^(n)) contains a nonstandard ideal [6, p. 189], and the problem seems to go back to Silov (a proposed solution appearing in the literature [6, p. 205] is in error). Interest has also been focused upon the quotient algebras (^(i^n))//), where / is assumed to be nonstandard, since these algebras are representative of all radical Banach algebras with power series generators [1]. Our result is the following:
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