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A130806
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Period 6: 1,4,3,-1,-4,-3.
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2
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1, 4, 3, -1, -4, -3, 1, 4, 3, -1, -4, -3, 1, 4, 3, -1, -4, -3, 1, 4, 3, -1, -4, -3, 1, 4, 3, -1, -4, -3, 1, 4, 3, -1, -4, -3, 1, 4, 3, -1, -4, -3, 1, 4, 3, -1, -4, -3, 1, 4, 3
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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LINKS
| Index to sequences with linear recurrences with constant coefficients, signature (1,-1).
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FORMULA
| a(n)=(1/6)*{-4*(n mod 6)-[(n+1) mod 6]+3*[(n+2) mod 6]+4*[(n+3) mod 6]+[(n+4) mod 6]-3*[(n+5) mod 6]}, with n>=0. - Paolo P. Lava (paoloplava(AT)gmail.com), Aug 28 2007
a(n) = a(n-1)-a(n-2) = A010892(n)+3*A010892(n-1). G.f.: (1+3*x)/(1-x+x^2). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 15 2009]
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PROG
| (PARI) a(n)=[1, 4, 3, -1, -4, -3][n%6+1] \\ Charles R Greathouse IV, Jun 02 2011
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CROSSREFS
| Sequence in context: A119505 A201518 A168616 * A200490 A016499 A066204
Adjacent sequences: A130803 A130804 A130805 * A130807 A130808 A130809
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KEYWORD
| sign,easy,less
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AUTHOR
| Paul Curtz (bpcrtz(AT)free.fr), Jul 16 2007
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EXTENSIONS
| Edited by N. J. A. Sloane (njas(AT)research.att.com), Sep 15 2007
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