A152506 1/5 of the number of permutations of 4 indistinguishable copies of 1..n with exactly 4 local maxima.

0, 1, 3277, 2483739, 1156102209, 443469188267, 156475306087585, 53194863262703203, 17785402102372820321, 5902647043581987876939, 1952635794694419540863057, 645038537405519790637628675, 212955626342843141187623423793, 70288152907297654332280282998411

Offset

1,3

Links

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

Prog

(PARI) \\ PeaksBySig defined in A334774.
a(n) = {PeaksBySig(vector(n, i, 4), [3])[1]/5} \\ Andrew Howroyd, May 12 2020

Crossrefs

Cf. A152504, A334774.

Sequence in context: A244626 A270204 A293626 * A309284 A015326 A252074

Adjacent sequences: A152503 A152504 A152505 * A152507 A152508 A152509

Keyword

nonn

Author

R. H. Hardin, Dec 06 2008

Extensions

Terms a(8) and beyond from Andrew Howroyd, May 12 2020

Status

approved