cp's OEIS Frontend

A190920 Number of permutations of n copies of 1..5 introduced in order 1..5 with no element equal to another within a distance of 1.

%I A190920 #17 Oct 05 2023 06:37:34
%S A190920 1,329,163386,98371884,66218360625,47940557125969,36533294879349056,
%T A190920 28920026907938624194,23575497690601916022516,
%U A190920 19672658572012343899666292,16730974132035148942028759656,14455459908454408519322566567054
%N A190920 Number of permutations of n copies of 1..5 introduced in order 1..5 with no element equal to another within a distance of 1.
%H A190920 Seiichi Manyama, <a href="/A190920/b190920.txt">Table of n, a(n) for n = 1..334</a> (terms 1..55 from R. H. Hardin)
%F A190920 a(n) ~ 25 * sqrt(5) * 2^(10*n-7) / (27 * Pi^2 * n^2). - _Vaclav Kotesovec_, Nov 24 2018
%e A190920 Some solutions for n=2
%e A190920 ..1....1....1....1....1....1....1....1....1....1....1....1....1....1....1....1
%e A190920 ..2....2....2....2....2....2....2....2....2....2....2....2....2....2....2....2
%e A190920 ..3....3....3....3....3....3....3....3....1....3....3....3....3....3....3....3
%e A190920 ..4....4....2....1....4....4....4....4....3....4....4....4....1....4....4....4
%e A190920 ..1....5....4....4....1....5....3....5....4....5....3....5....4....3....2....5
%e A190920 ..5....3....5....2....5....2....4....4....5....2....2....3....5....2....3....2
%e A190920 ..2....2....4....3....4....1....5....5....2....4....5....5....4....5....5....5
%e A190920 ..5....1....3....5....2....3....1....1....4....3....1....4....2....1....4....4
%e A190920 ..3....4....5....4....3....4....5....3....5....5....5....1....5....4....1....3
%e A190920 ..4....5....1....5....5....5....2....2....3....1....4....2....3....5....5....1
%Y A190920 Column k=5 of A322013.
%Y A190920 Cf. A000012 (b=2), A190917 (b=3), A190918 (b=4), A190923 (b=6), A190927 (b=7), A190932 (b=8), A321987 (b=9).
%K A190920 nonn
%O A190920 1,2
%A A190920 _R. H. Hardin_, May 23 2011