%I #5 Apr 07 2021 19:26:34
%S 1,2,6,24,120,624,4176,31564,271972,2654974,28246094,320329694,
%T 4116736768,54680271878
%N Number of permutations of 0..n-1 with all sums of 2 through 4 adjacent terms squared respectively unique.
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 11 2008