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%I #3 Mar 31 2012 12:35:18
%S 0,120,23580,1041140,31611675,836679060
%N Number of permutations of 5 indistinguishable copies of 1..n arranged in a circle with exactly 3 adjacent element pairs in decreasing order.
%K nonn
%O 1,2
%A _R. H. Hardin_ May 21 2009