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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
OFFSET
1,6
LINKS
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 20 2009
EXTENSIONS
Terms a(10) and beyond from Andrew Howroyd, May 13 2020
STATUS
approved