Absolutely 2-Summing Operators, 2 a Symmetric Sequence Space
نویسنده
چکیده
Pietsch [5] introduced the concept of absolutely summing operators in Banach spaces and later in [6] extended this concept to absolutely p-summing operators. At the background of these concepts are the sequence spaces I p and their duality theory. The object of the present paper is to extend the above concept to abstract sequence spaces 2. The sequence spaces 2 involved are described in Section 2; the absolutely 2-summing operators are studied in Section3 while Section4 discusses the interesting special case 2=n(~b), a sequence space which includes for special q5 the P and l ~ spaces and was introduced in the literature by Sargent [10].
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