A179957 - OEIS

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A179957

Number of permutations of 1..n such that |p(i)-p(i-1)|>= 4 for i>1.

%I #10 Oct 27 2014 10:21:37

%S 1,1,0,0,0,0,0,0,2,72,1496,25384,399848,6231544,99133496,1634227958,

%T 28120703888,506599465896,9562489659952,189055933191880,

%U 3911226769004280

%N Number of permutations of 1..n such that |p(i)-p(i-1)|>= 4 for i>1.

%K nonn

%O 0,9

%A _R. H. Hardin_, Aug 03 2010

%E a(0), a(19)-a(20) from _Alois P. Heinz_, Oct 27 2014