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A162595 G.f. is the polynomial (1-x^3) * (1-x^6) * (1-x^9) * (1-x^12) * (1-x^15) * (1-x^18) * (1-x^21) / (1-x)^7. 1

%I

%S 1,7,28,83,203,434,839,1499,2513,3997,6082,8911,12635,17408,23381,

%T 30696,39480,49839,61852,75565,90985,108075,126750,146874,168259,

%U 190666,213808,237355,260941,284173,306641,327929,347627,365343,380715,393423

%N G.f. is the polynomial (1-x^3) * (1-x^6) * (1-x^9) * (1-x^12) * (1-x^15) * (1-x^18) * (1-x^21) / (1-x)^7.

%C This is a row of the triangle in A162499. Only finitely many terms are nonzero.

%H G. C. Greubel, <a href="/A162595/b162595.txt">Table of n, a(n) for n = 0..77</a> (complete row)

%t CoefficientList[Series[Times@@(1-x^(3*Range[7]))/(1-x)^7,{x,0,40}],x] (* _Harvey P. Dale_, Oct 08 2015 *)

%o (PARI) x='x+O('x^50); A = prod(k=1, 7, (1-x^(3*k)))/(1-x)^7; Vec(A) \\ _G. C. Greubel_, Jul 07 2018

%o (MAGMA) m:=50; R<x>:=PowerSeriesRing(Integers(), m); F:=(&*[(1-x^(3*k)): k in [1..7]])/(1-x)^7; Coefficients(R!(F)); // _G. C. Greubel_, Jul 07 2018

%Y Cf. A162499.

%K nonn

%O 0,2

%A _N. J. A. Sloane_, Dec 02 2009

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Last modified May 7 02:20 EDT 2021. Contains 343636 sequences. (Running on oeis4.)