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Bisection of imperfect numbers A132999.
2

%I #6 Feb 22 2017 02:24:19

%S 1,3,5,8,10,12,14,16,18,20,22,24,26,29,31,33,35,37,39,41,43,45,47,49,

%T 51,53,55,57,59,61,63,65,67,69,71,73,75,77,79,81,83,85,87,89,91,93,95,

%U 97,99,101,103,105,107,109,111,113,115,117

%N Bisection of imperfect numbers A132999.

%H G. C. Greubel, <a href="/A138829/b138829.txt">Table of n, a(n) for n = 1..1000</a>

%F G.f.: (-x^14 + x^13 - x^4 + x^3 + x + 1)/(x^2 - 2*x + 1). - _Alexander R. Povolotsky_, Apr 06 2008

%t CoefficientList[Series[(-x^14 + x^13 - x^4 + x^3 + x + 1)/(x^2 - 2*x + 1), {x, 0, 50}], x] (* _G. C. Greubel_, Feb 21 2017 *)

%o (PARI) x='x+O('x^50); Vec((-x^14 + x^13 - x^4 + x^3 + x + 1)/(x^2 - 2*x + 1)) \\ _G. C. Greubel_, Feb 21 2017

%Y Cf. A000396, A099057, A099058, A132999.

%K easy,nonn

%O 1,2

%A _Omar E. Pol_, Apr 06 2008