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A172254
1 followed by period 4: repeat [-1, 3, -2, -1].
0
1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1, -1, 3, -2, -1
OFFSET
1,3
FORMULA
From Wesley Ivan Hurt, Jul 08 2016: (Start)
G.f.: x*(1-x+3*x^2-2*x^3-2*x^4)/(1-x^4).
a(n) = a(n-4) for n>5.
a(n) = (5*I^(2*n) - 1 - (4-I)*I^(-n) - (4+I)*I^n)/4 for n>1. (End)
MAPLE
1, seq(op([-1, 3, -2, -1]), n=1..30); # Wesley Ivan Hurt, Jul 08 2016
MATHEMATICA
Join[{1}, PadRight[{}, 100, {-1, 3, -2, -1}]] (* Wesley Ivan Hurt, Jul 08 2016 *)
PROG
(Magma) [1] cat &cat [[-1, 3, -2, -1]^^30]; // Wesley Ivan Hurt, Jul 08 2016
(PARI) Vec(x*(1-x+3*x^2-2*x^3-2*x^4)/(1-x^4) + O(x^99)) \\ Altug Alkan, Jul 08 2016
CROSSREFS
Sequence in context: A231820 A010268 A181657 * A053542 A087284 A262311
KEYWORD
sign,less,easy
AUTHOR
L. Naing (lnaing.yangon_univ(AT)yahoo.in), Jan 29 2010
EXTENSIONS
Edited by Joerg Arndt, Sep 04 2011
STATUS
approved