تعمیم الگوریتم بوخبرگر در جبرهای تفاضلی نسبت به ترتیب­های چندگانه

نویسندگان
دانشگاه دامغان
چکیده
پایه­­ی گربنر نسبت به چند ترتیب برای یک مدول تفاضلی، مهمترین ابزار برای یافتن چندجمله­ای بعد دستگاه­های دیفرانسیلی و تفاضلی است. در این مقاله، الگوریتمی برای محاسبه­ی این پایه­ی گربنر، ارایه شده است. برای این منظور، ابتدا برای هر عضو از یک مدول تفاضلی نوعی نمایش، موسوم به نمایش نسبت به چند ترتیب، معرفی می کنیم. سپس با استفاده از این نمایش، اثباتی برای تعمیم قضیه­ی بوخبرگر در مدول­های تفاضلی متناهی مولد، ارایه می­دهیم. همچنین شرط لازم و کافی برای وجود پایه­ی گربنر نسبت به چند ترتیب را برای یک مدول تفاضلی بیان می­کنیم. در ادامه، الگوریتمی برای محاسبه­ی پایه­ی­ گربنر یک زیر مدول تفاضلی متناهی مولد نسبت به چند ترتیب، ارایه می­شود.


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کلیدواژه‌ها

عنوان مقاله English

Generalization of Buchberger’s Algorithm with Respect to Several Orderings on Difference Modules

نویسندگان English

hamzeh harfsheno
abdolali basiri
sajjad rahmany
Damghan university
چکیده English

Grobner basis with respect to several orderings is a powerful tool to compute multivariate difference dimension polynomials. In this paper, an algorithm for computing a Grobner basis of a difference module over a ground difference field with respect to several term orderings is presented. In this direction, a representation of an element of a difference module with respect to several term orderings is introduced. Based on such representation, we generalize the Buchberger theorem to the case of free modules over difference rings with several term orderings associated with a partition of the set of variables. Furthermore, the necessary and sufficient condition is given for the existence of a Grobner basis with respect to several term orderings. In the sequel, we present our implementation of the algorithm on Maple.



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کلیدواژه‌ها English

Difference ring
Difference module
Groebner basis
Buchberger algorithm
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