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A032251 "DHK" (bracelet, identity, unlabeled) transform of 2,2,2,2,... 1
1, 2, 3, 6, 9, 18, 45, 118, 336, 954, 2695, 7590, 21321, 59890, 168273, 473966, 1337476, 3785154, 10738373, 30546502, 87099571, 248937978, 712995733, 2046236598, 5883318437, 16944709370, 48880145967, 141211579446 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Andrew Howroyd, Table of n, a(n) for n = 0..500

C. G. Bower, Transforms (2)

PROG

(PARI)

DHK(p, n)={my(q=((1+p)^2/(1-subst(p, x, x^2))-1)/2); p + (p^2-subst(p, x, x^2))/2 + sum(d=1, n, moebius(d)*(log(subst(1/(1+O(x*x^(n\d))-p), x, x^d))/d - subst(q + O(x*x^(n\d)), x, x^d)))/2}

seq(n)={Vec(1 + DHK(2*x/(1-x) + O(x*x^n), n))} \\ Andrew Howroyd, Sep 21 2018

CROSSREFS

Sequence in context: A018582 A018619 A018638 * A018679 A018741 A161704

Adjacent sequences:  A032248 A032249 A032250 * A032252 A032253 A032254

KEYWORD

nonn

AUTHOR

Christian G. Bower

EXTENSIONS

a(0)=1 prepended by Andrew Howroyd, Sep 21 2018

STATUS

approved

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Last modified October 22 23:18 EDT 2018. Contains 316518 sequences. (Running on oeis4.)