%I A151587
%S A151587 0,4,11565,2580588,229630758,12719963448,531411968223,18510889687040
%N A151587 Number of permutations of 2 indistinguishable copies of 1..n arranged 
               in a circle with exactly 6 adjacent element pairs in decreasing order.
%Y A151587 Sequence in context: A072724 A116271 A058417 this_sequence A134368 A152840 
               A003832
%Y A151587 Adjacent sequences: A151584 A151585 A151586 this_sequence A151588 A151589 
               A151590
%K A151587 nonn
%O A151587 3,2
%A A151587 Ron Hardin (rhhardin(AT)att.net) May 21 2009