A066315 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

A066315

Number of aperiodic bracelets (or necklaces) with n red and blue beads such that the beads switch colors when bracelet is turned over.

1, 1, 3, 7, 20, 51, 154, 460, 1476, 4860, 16544, 57321, 202059, 720370, 2593470, 9408000, 34350506, 126108252, 465200332, 1723341185, 6408356052, 23911255544, 89495909408, 335916703284, 1264114452975, 4768464107355

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,3

LINKS

Table of n, a(n) for n=1..26.

Index entries for sequences related to bracelets

FORMULA

Moebius transform of A006080(n+1).

MATHEMATICA

a[n_] := Sum[MoebiusMu[n/d] A006080[d + 1], {d, Divisors[n]}];

Array[a, 26] (* Jean-François Alcover, Aug 28 2019 *)

CROSSREFS

Sequence in context: A281971 A230352 A271894 * A339061 A058499 A003097

Adjacent sequences: A066312 A066313 A066314 * A066316 A066317 A066318

KEYWORD

nonn

AUTHOR

Christian G. Bower, Dec 13 2001

STATUS

approved