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%I #5 Apr 07 2021 19:36:37
%S 1,2,6,24,120,720,4608,35104,314876,2945156,32435238,381940958,
%T 4765565464,65551559472
%N Number of permutations of 2..n+1 with all sums of 2 through 3 adjacent terms squared respectively unique.
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 11 2008