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%I #14 Dec 12 2023 08:35:46
%S 0,2,8,4,6,6,4,8,2,0,0,2,8,4,6,6,4,8,2,0,0,2,8,4,6,6,4,8,2,0,0,2,8,4,
%T 6,6,4,8,2,0,0,2,8,4,6,6,4,8,2,0,0,2,8,4,6,6,4,8,2,0,0,2,8,4,6,6,4,8,
%U 2,0,0,2,8,4,6,6,4,8,2,0,0,2,8,4,6,6,4,8,2,0,0,2,8,4,6,6,4,8,2,0,0,2,8,4,6
%N Palindromic period 10: repeat 0, 2, 8, 4, 6, 6, 4, 8, 2, 0.
%H <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (1,-1,1,-1,1,-1,1,-1,1).
%F From _Chai Wah Wu_, Jun 04 2016: (Start)
%F 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) + a(n-9) for n > 8.
%F G.f.: 2*x*(1 + 3*x - x^2 + 4*x^3 - x^4 + 3*x^5 + x^6)/((1 - x)*(1 - x + x^2 - x^3 + x^4)*(1 + x + x^ 2 + x^3 + x^4)). (End)
%o (PARI) a(n)=[0, 2, 8, 4, 6, 6, 4, 8, 2, 0][n%10+1] \\ _Charles R Greathouse IV_, Jul 13 2016
%Y Cf. A117616.
%K nonn,easy
%O 0,2
%A _Paul Curtz_, May 06 2008