A152503 1/8 of the number of permutations of 3 indistinguishable copies of 1..n with exactly 6 local maxima.

0, 0, 0, 925, 5134608, 7080780596, 5503883684118, 3175651343215500, 1543855504958661492, 676391857775294288488, 277604477433374392213008, 109265969423431070616562496, 41856404659462959845867172864, 15752452465692536904424614273024, 5860017184412283112523269770190848

Offset

1,4

Links

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

Prog

(PARI) \\ PeaksBySig defined in A334774.
a(n) = {PeaksBySig(vector(n, i, 3), [5])[1]/8} \\ Andrew Howroyd, May 12 2020

Crossrefs

Cf. A152499, A334774.

Sequence in context: A229641 A147548 A116989 * A099688 A257485 A255106

Adjacent sequences: A152500 A152501 A152502 * A152504 A152505 A152506

Keyword

nonn

Author

R. H. Hardin, Dec 06 2008

Extensions

Terms a(9) and beyond from Andrew Howroyd, May 12 2020

Status

approved