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%I #8 Apr 28 2021 01:25:21
%S 1,8,28,82,500,2740,15040,100630,704000,5310960,44616536
%N Number of arrays of length n that are sums of 3 consecutive elements of length n+2 permutations of 0..n+1, and no two consecutive rises or falls in the latter permutation.
%C Column 3 of A229717.
%e Some solutions for n=4:
%e 8 9 3 12 6 6 10 8 8 9 10 8 8 9 7 6
%e 12 8 8 9 11 9 9 6 9 12 12 9 3 11 6 7
%e 8 11 9 8 8 6 4 10 4 8 7 12 6 7 10 4
%e 7 6 12 3 9 9 5 7 7 6 5 7 7 6 8 9
%K nonn,more
%O 1,2
%A _R. H. Hardin_, Sep 27 2013