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1/21 of the number of permutations of 6 indistinguishable copies of 1..n with exactly 5 local maxima.
1

%I #6 May 12 2020 18:19:23

%S 0,5,285365,3328373375,23122804891093,132106319858700205,

%T 697701196338306192217,3568377130807709398000279,

%U 18013809185839252548978200161,90462608845509339028810174966669,453352973288072573009512458761236141,2270154484704085339079608424120307696559

%N 1/21 of the number of permutations of 6 indistinguishable copies of 1..n with exactly 5 local maxima.

%H Andrew Howroyd, <a href="/A152516/b152516.txt">Table of n, a(n) for n = 1..200</a>

%o (PARI) \\ PeaksBySig defined in A334774.

%o a(n) = {PeaksBySig(vector(n,i,6), [4])[1]/21} \\ _Andrew Howroyd_, May 12 2020

%Y Cf. A152513, A334774.

%K nonn

%O 1,2

%A _R. H. Hardin_, Dec 06 2008

%E Terms a(7) and beyond from _Andrew Howroyd_, May 12 2020