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%I #15 Dec 12 2023 08:05:09
%S -2,4,-2,4,-2,-2,1,1,-2,-2,4,-2,4,-2,-2,1,1,-2,-2,4,-2,4,-2,-2,1,1,-2,
%T -2,4,-2,4,-2,-2,1,1,-2,-2,4,-2,4,-2,-2,1,1,-2,-2,4,-2,4,-2,-2,1,1,-2,
%U -2,4,-2,4,-2,-2,1,1,-2,-2,4,-2,4,-2,-2,1,1,-2,-2,4,-2,4,-2,-2,1,1,-2,-2,4,-2
%N Period 9: repeat [-2,4,-2,4,-2,-2,1,1,-2].
%C Rotated by 7 places, the period is palindromic: 1,-2,-2,4,-2,4,-2,-2,1.
%H <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (-1,-1,-1,-1,-1,-1,-1,-1).
%F a(n)= A158090(n)-2 = A158090(n)-A007395(n+1).
%F G.f.: (-2+2*x+4*x^3+x^6+2*x^4+2*x^7)/((1+x+x^2)*(x^6+x^3+1)). a(n)= -a(n-1)-a(n-2)-a(n-3)-a(n-4)-a(n-5)-a(n-6)-a(n-7)-a(n-8). - _R. J. Mathar_, Apr 09 2009
%t PadRight[{},120,{-2,4,-2,4,-2,-2,1,1,-2}] (* _Harvey P. Dale_, Dec 11 2018 *)
%o (PARI) a(n)=[-2,4,-2,4,-2,-2,1,1,-2][n%9+1] \\ _Charles R Greathouse IV_, Jul 13 2016
%Y Cf. A156346.
%K sign,easy,less
%O 0,1
%A _Paul Curtz_, Mar 13 2009
%E Edited and extended by _R. J. Mathar_, Apr 09 2009