OFFSET
0,9
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..1000
C. G. Bower, Transforms (2)
FORMULA
"CGK" (necklace, element, unlabeled) transform of 1, 0, 1, 0, ... (odds).
G.f.: 1 + Sum_{k>=1} (k-1)! * x^(k^2) / (Product_{j=1..k} 1-x^(2*j)). - Andrew Howroyd, Sep 13 2018
PROG
(PARI) seq(n)=[subst(serlaplace(p/y), y, 1) | p <- Vec(y-1+prod(k=1, ceil(n/2), 1 + x^(2*k-1)*y + O(x*x^n)))] \\ Andrew Howroyd, Sep 13 2018
(PARI) seq(n)={Vec(1 + sum(k=1, sqrtint(n), my(r=k^2); (k-1)! * x^r / prod(j=1, k, 1 - x^(2*j) + O(x*x^(n-r)))))} \\ Andrew Howroyd, Sep 13 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(0)=1 prepended by Andrew Howroyd, Sep 13 2018
STATUS
approved