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%I #6 Nov 02 2013 19:40:47
%S 1,70,34650,59789280,266337847482,2554877633330088,
%T 46673357620120575102,1485635287258589886509256
%N Number of permutations of 4 copies of 1..n avoiding adjacent step pattern up, down, down, down.
%K nonn
%O 1,2
%A _R. H. Hardin_, May 10 2010
%E a(8) from _Alois P. Heinz_, Nov 02 2013