%I #9 Apr 16 2023 22:13:11
%S 1,1,1,2,2,2,0,0,0,1,1,1,2,2,2,0,0,0,1,1,1,2,2,2,0,0,0,1,1,1,2,2,2,0,
%T 0,0,1,1,1,2,2,2,0,0,0,1,1,1,2,2,2,0,0,0,1,1,1,2,2,2,0,0,0,1,1,1,2,2,
%U 2,0,0,0,1,1,1,2,2,2,0,0,0,1,1,1,2,2,2,0,0,0,1,1,1,2,2,2,0,0,0,1,1,1,2,2,2
%N n modulo 3 repeated 3 times.
%C Periodic with length 3^2=9.
%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (1, 0, -1, 1, 0, -1, 1).
%F G.f.: (1 + 2*x^3)*(1 - x^3)/((1 - x)*(1 - x^9)).
%F a(n) = (1 + floor(n/3)) mod 3.
%F a(n) = A010872(A002264(n+3)).
%F a(n) = 1+floor(n/3)-3*floor((n+3)/9).
%F a(n) = (((n+3) mod 9)-(n mod 3))/3.
%F a(n) = ((n+3-(n mod 3))/3) mod 3.
%F a(n) = binomial(n+3,n) mod 3 = binomial(n+3,3) mod 3.
%Y Cf. A000040, A133620-A133625, A133630, A038509, A133634-A133636.
%Y Cf. A133883, A133880, A133890, A133900, A133910.
%K nonn,easy
%O 0,4
%A _Hieronymus Fischer_, Oct 10 2007
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