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%I #49 Sep 10 2022 07:33:18
%S 0,1,32,33,64,65,96,97,128,129,160,161,192,193,224,225,256,257,288,
%T 289,320,321,352,353,384,385,416,417,448,449,480,481,512,513,544,545,
%U 576,577,608,609,640,641,672,673,704,705,736,737,768,769,800,801,832,833,864,865
%N Numbers congruent to {0, 1} mod 32.
%C Numbers n such that n^2 - n is divisible by 32.
%H Vincenzo Librandi, <a href="/A151983/b151983.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,-1).
%F From _Bruno Berselli_, Jan 26 2011: (Start)
%F G.f.: (1+31*x)*x^2/((1+x)*(1-x)^2).
%F a(n) = a(n-1) + a(n-2) - a(n-3) for n > 3.
%F a(n) = (32*n - 15*(-1)^n - 47)/2.
%F Sum_{k=1..n} a(k) == 0 (mod A004526(n)) for n > 1. (End)
%F a(n+1) = Sum_{k>=0} A030308(n,k)*b(k) with b(0)=1, b(k)=2^(k+4) for k > 0. - _Philippe Deléham_, Oct 16 2011
%F E.g.f.: 31 + ((32*x - 47)*exp(x) - 15*exp(-x))/2. - _David Lovler_, Sep 10 2022
%t Flatten[{#,#+1}&/@(32Range[0,35])] (* _Harvey P. Dale_, Mar 11 2011 *)
%t CoefficientList[Series[(1 + 31 x) x / ((1 + x) (1 - x)^2), {x, 0, 40}], x] (* _Vincenzo Librandi_, Jun 19 2013 *)
%o (PARI) a(n)=(32*n-15*(-1)^n-47)/2 \\ _Charles R Greathouse IV_, Oct 16 2015
%Y Cf. A004526, A030308, A070454.
%K nonn,easy
%O 1,3
%A _N. J. A. Sloane_, Aug 23 2009