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A144110
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Period 6: repeat [2, 2, 2, 1, 1, 1].
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1
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2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1
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OFFSET
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0,1
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COMMENTS
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a(n) = 2 for n = 0,1,2 modulo 6; a(n) = 1 for n = 3,4,5 modulo 6.
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LINKS
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FORMULA
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G.f.: (1+2*x^3)/((1-x)*(1+x)*(1-x+x^2)); a(n) = 3/2-(-1)^n/6-A057079(n)/3. [R. J. Mathar, Sep 17 2008]
a(n) = a(n-1) - a(n-3) + a(n-4) for n>3; a(n) = 1 + mod(floor((-n-1)/3), 2); a(n) = A088911(n) + 1. - Wesley Ivan Hurt, Sep 04 2014
a(n) = (9 + cos(n*Pi) + 2*cos(n*Pi/3) + 2*sqrt(3)*sin(n*Pi/3))/6. - Wesley Ivan Hurt, Jun 23 2016
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MAPLE
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MATHEMATICA
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Table[1 + Mod[Floor[(-n - 1)/3], 2], {n, 0, 100}] (* Wesley Ivan Hurt, Sep 04 2014 *)
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PROG
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(Magma) [1+(Floor((-n-1)/3) mod 2) : n in [0..100]]; // Wesley Ivan Hurt, Sep 04 2014
(PARI) a(n)=[2, 2, 2, 1, 1, 1][n%6+1] \\ Edward Jiang, Sep 04 2014
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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