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A032285
"DIK" (bracelet, indistinct, unlabeled) transform of 4,4,4,4...
1
4, 14, 40, 125, 412, 1540, 6080, 25580, 111020, 494066, 2231960, 10201365, 47012620, 218126120, 1017565328, 4769086955, 22440958180, 105967383690, 501941663240, 2384203613501, 11353304737740, 54186129705260, 259150824770720, 1241763877376990, 5960465454101812
OFFSET
1,1
FORMULA
G.f.: (2*x*(2+5*x+x^2)/((1-x)*(1-5*x^2)) + Sum_{d>0} phi(d)*log((1-x^d)/(1-5*x^d))/d)/2. - Andrew Howroyd, Jun 20 2018
PROG
(PARI) seq(n)={Vec(2*x*(2+5*x+x^2)/((1-x)*(1-5*x^2)) + sum(d=1, n, eulerphi(d)/d*log((1-x^d)/(1-5*x^d) + O(x*x^n))))/2} \\ Andrew Howroyd, Jun 20 2018
CROSSREFS
Cf. A032283.
Sequence in context: A072674 A202900 A238117 * A196451 A196480 A326008
KEYWORD
nonn
EXTENSIONS
Terms a(22) and beyond from Andrew Howroyd, Jun 20 2018
STATUS
approved