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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
0, 0, 0, 0, 0, 40272, 62954948, 24342647424, 5320007368884, 848044852469680, 111078667024032048, 12769013592631944576, 1340902091662029846456, 132008300342568131914656, 12398363733385845967412220, 1124539850663707285433353472, 99357839137277548804214431980 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..200

PROG

(PARI) \\ CircPeaksBySig defined in A334778.

a(n) = {CircPeaksBySig(vector(n, i, 2), [6])[1]} \\ Andrew Howroyd, May 13 2020

CROSSREFS

Column 6 of A334778.

Cf. A159716.

Sequence in context: A236253 A076778 A172863 * A127228 A269126 A168359

Adjacent sequences:  A159717 A159718 A159719 * A159721 A159722 A159723

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 20 2009

EXTENSIONS

Terms a(10) and beyond from Andrew Howroyd, May 13 2020

STATUS

approved

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Last modified December 3 21:17 EST 2021. Contains 349468 sequences. (Running on oeis4.)