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A153990
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Period 6: repeat [1, 2, 5, 4, 7, 8].
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3
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1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2, 5, 4, 7, 8, 1, 2
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OFFSET
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0,2
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COMMENTS
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Shares digits with other 6-periodic sequences, see the list in A153130.
Also the decimal expansion of the constant 13942/111111. [R. J. Mathar, Jan 23 2009]
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LINKS
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FORMULA
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a(6n+0) + a(6n+5) = a(6n+1) + a(6n+4) = a(6n+2) + a(6n+3) = 9.
G.f.: (1+2*x+5*x^2+4*x^3+7*x^4+8*x^5)/((1-x)*(1+x)*(1+x+x^2)*(x^2-x+1)). [R. J. Mathar, Jan 23 2009]
a(n) = (27-cos(n*Pi)-8*sqrt(3)*cos((1-4*n)*Pi/6)-16*sin((1+2*n)*Pi/6))/6.
a(n) = a(n-6) for n>5. (End)
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MAPLE
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MATHEMATICA
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PadRight[{}, 120, {1, 2, 5, 4, 7, 8}] (* Harvey P. Dale, Nov 08 2017 *)
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PROG
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(Magma) &cat[[1, 2, 5, 4, 7, 8]: n in [0..20]]; // Wesley Ivan Hurt, Jun 17 2016
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CROSSREFS
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KEYWORD
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nonn,easy,less
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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