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A130974 Period 6: repeat [1, 1, 1, 3, 3, 3]. 3
1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1, 3, 3, 3, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

Terms of the simple continued fraction of 3/(sqrt(35)-4). Decimal expansion of 1003/9009. - Paolo P. Lava, Aug 05 2009

LINKS

Table of n, a(n) for n=0..104.

Index entries for linear recurrences with constant coefficients, signature (1,0,-1,1).

FORMULA

G.f.: (1+3*x^3)/((1-x)*(1+x)*(1-x+x^2)). - R. J. Mathar, Nov 15 2007

a(n) = 2 - (2/3)*cos((1/3)*Pi*n) - (2/3)*3^(1/2)*sin((1/3)*Pi*n) + (1/3)*(-1)^(1+n). - R. J. Mathar, Nov 15 2007

a(n) = 2 - (-1)^floor(n/3). - Bruno Berselli, Jul 09 2013

a(n) = a(n-1) - a(n-3) + a(n-4) for n > 3. - Wesley Ivan Hurt, Jun 20 2016

MAPLE

A130974:=n->[1, 1, 1, 3, 3, 3][(n mod 6)+1]: seq(A130974(n), n=0..100); # Wesley Ivan Hurt, Jun 20 2016

MATHEMATICA

PadRight[{}, 100, {1, 1, 1, 3, 3, 3}] (* Wesley Ivan Hurt, Jun 20 2016 *)

PROG

(MAGMA) &cat [[1, 1, 1, 3, 3, 3]^^30]; // Wesley Ivan Hurt, Jun 20 2016

(PARI) a(n) = [1, 1, 1, 3, 3, 3][n%6+1]; \\ Jinyuan Wang, Feb 26 2020

CROSSREFS

Cf. A177957 (decimal expansion of (12+3*sqrt(35))/19). - Klaus Brockhaus, May 16 2010

Sequence in context: A126066 A177693 A131289 * A064353 A190906 A080311

Adjacent sequences:  A130971 A130972 A130973 * A130975 A130976 A130977

KEYWORD

nonn,easy

AUTHOR

Paul Curtz, Sep 28 2007

STATUS

approved

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Last modified August 5 22:07 EDT 2020. Contains 336214 sequences. (Running on oeis4.)