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 A008728 Molien series for 3-dimensional group [2,n ] = *22n. 6

%I

%S 1,2,3,4,5,6,7,8,9,10,12,14,16,18,20,22,24,26,28,30,33,36,39,42,45,48,

%T 51,54,57,60,64,68,72,76,80,84,88,92,96,100,105,110,115,120,125,130,

%U 135,140,145,150,156,162,168,174,180,186,192,198,204,210,217,224,231,238

%N Molien series for 3-dimensional group [2,n ] = *22n.

%C a(n) = A179052(n) for n < 100. [_Reinhard Zumkeller_, Jun 27 2010]

%H Vincenzo Librandi, <a href="/A008728/b008728.txt">Table of n, a(n) for n = 0..1000</a>

%H INRIA Algorithms Project, <a href="http://ecs.inria.fr/services/structure?nbr=193">Encyclopedia of Combinatorial Structures 193</a>

%H <a href="/index/Mo#Molien">Index entries for Molien series</a>

%H <a href="/index/Rec#order_12">Index entries for linear recurrences with constant coefficients</a>, signature (2, -1, 0, 0, 0, 0, 0, 0, 0, 1, -2, 1).

%F G.f.: 1/((1-x)^2*(1-x^10)).

%F a(n) = sum(floor(j/10), {j,0,n+10}), a(n-10) = (1/2)floor(n/10)*(2n-8-10*floor(n/10)). [_Mitch Harris_, Sep 08 2008]

%p 1/(1-x)^2/(1-x^10)

%t s=0;lst={};Do[AppendTo[lst,s+=n];AppendTo[lst,s+=n];AppendTo[lst,s+=n];AppendTo[lst,s+=n];AppendTo[lst,s+=n];AppendTo[lst,s+=n];AppendTo[lst,s+=n];AppendTo[lst,s+=n];AppendTo[lst,s+=n];AppendTo[lst,s+=n],{n,0,5!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Mar 14 2010 *)

%t CoefficientList[Series[1 / ((1 - x)^2 (1 - x^10)), {x, 0, 70}], x] (* _Vincenzo Librandi_, Jun 11 2013 *)

%Y Cf. A001840, A001972, A008724, A008725, A008726, A008727, A008732.

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_.

%E More terms from _Vladimir Joseph Stephan Orlovsky_, Mar 14 2010

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