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%I #5 Apr 07 2021 20:07:11
%S 1,2,6,24,120,608,3684,23136,174536,1409200,12672984,123070048,
%T 1287015142,14387894342,172259484314,2186934015808
%N Number of permutations of 0..n-1 with all sums of 4 adjacent terms unique.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 02 2008