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A159720 Number of permutations of 2 indistinguishable copies of 1..n arranged in a circle with exactly 6 local maxima. 2

%I

%S 0,0,0,0,0,40272,62954948,24342647424,5320007368884,848044852469680,

%T 111078667024032048,12769013592631944576,1340902091662029846456,

%U 132008300342568131914656,12398363733385845967412220,1124539850663707285433353472,99357839137277548804214431980

%N Number of permutations of 2 indistinguishable copies of 1..n arranged in a circle with exactly 6 local maxima.

%H Andrew Howroyd, <a href="/A159720/b159720.txt">Table of n, a(n) for n = 1..200</a>

%o (PARI) \\ CircPeaksBySig defined in A334778.

%o a(n) = {CircPeaksBySig(vector(n, i, 2), [6])[1]} \\ _Andrew Howroyd_, May 13 2020

%Y Column 6 of A334778.

%Y Cf. A159716.

%K nonn

%O 1,6

%A _R. H. Hardin_, Apr 20 2009

%E Terms a(10) and beyond from _Andrew Howroyd_, May 13 2020

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Last modified January 27 15:07 EST 2022. Contains 350607 sequences. (Running on oeis4.)