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%I #12 Jun 08 2021 15:22:21
%S 0,0,0,1,9993,44288275,216956034178,1368009041285362
%N Number of permutations of 4 copies of 1..n introduced in order 1..n with no element equal to another within a distance of 3.
%e Some solutions for n=5
%e ..1....1....1....1....1....1....1....1....1....1....1....1....1....1....1....1
%e ..2....2....2....2....2....2....2....2....2....2....2....2....2....2....2....2
%e ..3....3....3....3....3....3....3....3....3....3....3....3....3....3....3....3
%e ..4....4....4....4....4....4....4....4....4....4....4....4....4....4....4....4
%e ..5....5....5....5....5....5....5....5....5....1....5....5....5....5....1....5
%e ..1....1....2....1....1....1....1....2....1....5....2....2....2....1....5....1
%e ..2....3....1....2....2....3....3....3....3....2....3....1....3....2....3....3
%e ..4....2....3....4....4....2....4....1....2....3....4....4....4....4....4....4
%e ..3....4....5....3....5....4....2....4....5....4....5....3....1....3....2....2
%e ..1....5....4....1....3....5....1....2....4....5....1....2....2....5....1....5
%e ..2....1....1....5....2....3....3....5....3....1....3....5....3....2....5....1
%e ..5....3....2....4....4....2....5....1....1....2....4....1....5....1....4....4
%e ..3....2....3....2....1....1....2....4....2....4....5....4....4....3....3....2
%e ..4....5....4....3....5....5....4....3....4....3....1....3....2....5....2....3
%e ..1....4....5....5....3....4....3....5....5....5....3....5....1....2....5....5
%e ..5....3....2....1....4....2....5....2....1....1....2....1....5....4....1....4
%e ..3....1....3....4....2....1....1....1....2....4....5....4....3....1....4....1
%e ..2....5....1....3....5....3....4....4....4....3....4....2....4....3....3....2
%e ..4....2....4....2....1....4....2....5....5....5....1....3....1....5....2....5
%e ..5....4....5....5....3....5....5....3....3....2....2....5....5....4....5....3
%K nonn,more
%O 1,5
%A _R. H. Hardin_, May 21 2011