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A048065 Number of nonempty subsets of {1,2,...,n} in which exactly 1/5 of the elements are <= (n-4)/2. 0

%I

%S 0,0,0,0,0,5,15,30,70,105,213,286,558,720,1500,1935,4455,5775,13895,

%T 17876,42484,53859,124761,156065,357825,444015,1028500,1272155,

%U 3002795,3709043,8871603,10935267,26243427

%N Number of nonempty subsets of {1,2,...,n} in which exactly 1/5 of the elements are <= (n-4)/2.

%K nonn

%O 1,6

%A _Clark Kimberling_

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Last modified November 27 21:32 EST 2020. Contains 338684 sequences. (Running on oeis4.)