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A032277 Number of ways to partition n elements into pie slices each with an odd number of elements allowing the pie to be turned over. 1
1, 1, 2, 2, 3, 4, 5, 7, 9, 13, 16, 25, 31, 48, 64, 98, 133, 208, 291, 454, 657, 1021, 1510, 2358, 3545, 5535, 8442, 13200, 20319, 31835, 49353, 77435, 120711, 189673, 296854, 467159, 733363, 1155646, 1818594, 2869377, 4524081 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..500

C. G. Bower, Transforms (2)

FORMULA

"DIK" (bracelet, indistinct, unlabeled) transform of 1, 0, 1, 0, ... (odds)

G.f.: (x*(1 + x - x^4)/((1 - x)*(1 + x)*(1 - x^2 - x^4)) + Sum_{d>0} phi(d)*log((1 - x^(2*d))/(1 - x^d - x^(2*d)))/d)/2. - Andrew Howroyd, Jun 20 2018

PROG

(PARI) seq(n)={Vec(x*(1 + x - x^4)/((1 - x)*(1 + x)*(1 - x^2 - x^4)) + sum(d=1, n, eulerphi(d)/d*log((1-x^(2*d))/(1-x^d-x^(2*d)) + O(x*x^n))))/2} \\ Andrew Howroyd, Jun 20 2018

CROSSREFS

Sequence in context: A072493 A064324 A173090 * A205579 A089047 A133498

Adjacent sequences:  A032274 A032275 A032276 * A032278 A032279 A032280

KEYWORD

nonn

AUTHOR

Christian G. Bower

STATUS

approved

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Last modified October 20 19:34 EDT 2018. Contains 316401 sequences. (Running on oeis4.)