A159717 Number of permutations of 2 indistinguishable copies of 1..n arranged in a circle with exactly 3 local maxima.
0, 0, 6, 1192, 61830, 2150688, 62178928, 1629254640, 40346856234, 965510596600, 22606163844396, 521603874280248, 11911230805813846, 269907065756299440, 6079103449024019880, 136243494317831152480, 3040751938796332410018, 67621304208554979697224, 1499043510801269678080708
Offset: 1
Keywords
Links
- Andrew Howroyd, Table of n, a(n) for n = 1..200
Programs
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PARI
\\ CircPeaksBySig defined in A334778. a(n) = {CircPeaksBySig(vector(n, i, 2), [3])[1]} \\ Andrew Howroyd, May 13 2020
Extensions
Terms a(11) and beyond from Andrew Howroyd, May 13 2020