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A131532
Period 6: repeat [0, 0, 0, 0, 1, 1].
1
0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0
OFFSET
0,1
FORMULA
G.f.: -x^4/((x-1)*(x^2+x+1)*(x^2-x+1)). - R. J. Mathar, Nov 14 2007
From Wesley Ivan Hurt, Jun 19 2016: (Start)
a(n) = a(n-1) - a(n-2) + a(n-3) - a(n-4) + a(n-5) for n>4.
a(n) = sin(n*Pi/3)*(2*sin(n*Pi/3)-sqrt(3))/3. (End)
MAPLE
A131532:=n->[0, 0, 0, 0, 1, 1][(n mod 6)+1]: seq(A131532(n), n=0..100); # Wesley Ivan Hurt, Jun 19 2016
MATHEMATICA
PadRight[{}, 200, {0, 0, 0, 0, 1, 1}] (* Wesley Ivan Hurt, Jun 19 2016 *)
PROG
(PARI) a(n)=n%6>3 \\ Jaume Oliver Lafont, Aug 28 2009
(Magma) &cat[[0, 0, 0, 0, 1, 1]^^20]; // Wesley Ivan Hurt, Jun 19 2016
CROSSREFS
Sequence in context: A347412 A275926 A131533 * A353513 A085114 A286336
KEYWORD
nonn,easy
AUTHOR
Paul Curtz, Aug 26 2007
EXTENSIONS
Edited by N. J. A. Sloane, Sep 15 2007
STATUS
approved