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%I #7 Apr 18 2023 08:48:15
%S 1,80,6976,639552,60656016,5898286349,585487585760,59147199364720,
%T 6067259409345901,630842897289489196,66388460469198215359,
%U 7062901351795999772739,758832478269321359233282
%N Number of permutations of n copies of 1..7 introduced in order 1..7 with no element equal to another within a distance of 5.
%H R. H. Hardin, <a href="/A190931/b190931.txt">Table of n, a(n) for n = 1..25</a>
%e Some solutions for n=2
%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....5....5....5....5....5....5....5
%e ..6....6....6....6....6....6....6....6....6....6....6....6....6....6....6....6
%e ..1....7....7....1....7....7....7....1....7....1....7....7....7....7....7....7
%e ..7....2....1....7....1....1....1....7....1....7....1....1....1....2....1....1
%e ..2....1....2....2....2....2....3....3....2....3....2....2....2....3....3....2
%e ..3....3....4....3....3....3....2....4....3....2....4....4....3....1....4....3
%e ..4....4....3....5....5....4....5....2....4....5....3....5....5....4....2....5
%e ..5....5....5....6....6....5....6....5....6....6....6....6....4....5....5....6
%e ..6....6....7....4....4....6....7....6....7....4....5....7....6....7....6....7
%e ..7....7....6....7....7....7....4....7....5....7....7....3....7....6....7....4
%K nonn
%O 1,2
%A _R. H. Hardin_, May 23 2011
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