On the number of combinations without unit separation
نویسندگان
چکیده
منابع مشابه
On the number of combinations without certain separations
Abstract. In this paper we enumerate the number of ways of selecting k objects from n objects arrayed in a line such that no two selected ones are separated bym−1, 2m−1, · · · , pm−1 objects and provide three different formulas when m, p ≥ 1 and n ≥ pm(k − 1). Also, we prove that the number of ways of selecting k objects from n objects arrayed in a circle such that no two selected ones are sepa...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series A
سال: 1981
ISSN: 0097-3165
DOI: 10.1016/0097-3165(81)90006-6