%I A127697
%S A127697 0,0,0,0,0,2,32,368,3984,64904,947168
%N A127697 Number of permutations of {1,2,...,n} where adjacent elements differ 
               in value by 3 or more.
%C A127697 Equivalently, number of permutations of {1,2,...,n} where elements that 
               differ by 1 in value are neither in positions i and i+1 (adjacent), 
               or i and i+2.
%e A127697 Valid permutations of {1,...,6} are 415263 and 362514.
%Y A127697 Cf. A002464.
%Y A127697 Sequence in context: A053065 A091707 A060868 this_sequence A109772 A115418 
               A163952
%Y A127697 Adjacent sequences: A127694 A127695 A127696 this_sequence A127698 A127699 
               A127700
%K A127697 nonn
%O A127697 1,6
%A A127697 Richard Forster (gbrl01(AT)yahoo.co.uk), Apr 11 2007, Apr 26 2007