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%I #5 Apr 07 2021 20:11:51
%S 1,2,6,24,120,640,3924,28656,211984,1841052,16619224,170244216,
%T 1872923892,21777129140,280485621020,3762640368156
%N Number of permutations of floor(i*9/7), i=0..n-1, with all sums of 4 adjacent terms unique.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 02 2008