A334780 Total number of local maxima in all permutations of 2 indistinguishable copies of 1..n arranged in a circle.

1, 8, 168, 6336, 360000, 28728000, 3067243200, 422479411200, 72968229734400, 15446903472000000, 3933958530902400000, 1186723982675911680000, 418497083472072084480000, 170595438771094235458560000, 79604772050991371184000000000, 42160341403338557272473600000000

Offset

1,2

Links

Andrew Howroyd, Table of n, a(n) for n = 1..100

Formula

a(n) = Sum_{k=1..n} k*A334778(n,k).

Prog

(PARI) \\ CircPeaksBySig defined in A334778.
a(n)={my(u=CircPeaksBySig(vector(n, i, 2), [1..n])); sum(k=1, #u, k*u[k])}

Crossrefs

Cf. A334778.

Sequence in context: A254459 A254129 A359926 * A084941 A139564 A264113

Adjacent sequences: A334777 A334778 A334779 * A334781 A334782 A334783

Keyword

nonn

Author

Andrew Howroyd, May 13 2020

Status

approved