%I #8 Jan 09 2017 15:44:44
%S 1,1,2,6,24,120,720,5040,40320,282240,2903040,26853120,333849600,
%T 3802982400,55244851200,745007155200,12362073292800,192275074252800,
%U 3584572069478400,63107717389516800,1305169212624076800,25641537378199142400,582386191297118208000
%N Number of permutations of 1..n with no adjacent pair summing to n + 8.
%C If a(n,k) is the number of permutations of 1..n with no adjacent pair summing to n+k, then a(n,k) = a(n,k+1) for n+k even.
%F k = 8; m = max(0, floor((n-k+1)/2)); a(n,k) = Sum_{j=0..m} (-2)^j * binomial(m,j)*(n-j)!.
%K nonn
%O 0,3
%A _R. H. Hardin_, Feb 26 2010
%E Comment proved by William Keith, formula from _Max Alekseyev_, on the Sequence Fans Mailing List
%E More terms from _Alois P. Heinz_, Jan 09 2017
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