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%I #14 Nov 24 2018 09:04:26
%S 1,721315,1133879136649,2536823683737613858,6945222145021508480249929,
%T 21671513613423101256198918372909,
%U 74115215422015289392187745053216373265,271259741131895052775392614041761701799270286
%N Number of permutations of n copies of 1..8 introduced in order 1..8 with no element equal to another within a distance of 1
%H Seiichi Manyama, <a href="/A190932/b190932.txt">Table of n, a(n) for n = 1..149</a> (terms 1..20 from R. H. Hardin)
%F a(n) ~ 2 * 7^(8*n-2) / (1215 * sqrt(3) * Pi^(7/2) * n^(7/2)). - _Vaclav Kotesovec_, Nov 24 2018
%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 ..1....3....3....1....1....1....3....1....3....3....1....1....1....1....3....1
%e ..3....1....1....3....3....3....1....3....1....1....3....3....3....3....1....2
%e ..4....4....4....4....4....4....4....4....2....4....4....4....4....4....4....3
%e ..5....5....5....3....5....5....5....5....3....5....5....5....2....5....5....4
%e ..6....4....3....5....6....6....6....4....4....3....4....6....5....6....2....5
%e ..5....6....6....6....7....7....2....6....5....6....5....7....6....5....6....6
%e ..6....7....7....7....5....2....3....7....6....5....6....8....7....7....7....7
%e ..3....8....8....8....6....8....5....8....7....2....7....7....5....8....3....8
%e ..2....5....2....7....8....6....7....3....4....7....2....5....8....3....8....3
%e ..7....2....6....8....2....3....6....6....6....6....6....2....3....6....4....5
%e ..8....8....7....4....3....4....8....5....8....7....7....3....7....4....6....7
%e ..4....3....4....6....4....5....7....8....5....8....8....4....4....2....7....4
%e ..8....7....5....5....8....8....8....2....7....4....3....8....8....7....8....8
%e ..7....6....8....2....7....7....4....7....8....8....8....6....6....8....5....6
%Y Cf. A000012, A190917, A190918, A190920, A190923, A190927, A321987.
%K nonn
%O 1,2
%A _R. H. Hardin_ May 23 2011
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