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A101000
Period 3: repeat [0, 1, 3].
4
0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3, 0, 1, 3
OFFSET
0,3
FORMULA
a(n) = floor((n mod 3)*3/2). - Reinhard Zumkeller, Jun 23 2007
a(n) = 4 - a(n-1) - a(n-2) for n > 1. - Reinhard Zumkeller, Apr 13 2008
G.f.: x*(1+3*x)/(1-x^3). - Jaume Oliver Lafont, Mar 24 2009
a(n) = 2^(n mod 3) - 1. - Wesley Ivan Hurt, Apr 16 2014
a(n) = (7*a(n-1) + 2)*(3 - a(n-1))/6 for n > 0. - Nicolas Bělohoubek, Oct 09 2024
MAPLE
A101000:=n->2^(n mod 3) - 1; seq(A101000(n), n=0..100); # Wesley Ivan Hurt, Apr 16 2014
MATHEMATICA
PadRight[{}, 120, {0, 1, 3}] (* Harvey P. Dale, Apr 28 2012 *)
Table[2^Mod[n, 3] - 1, {n, 0, 100}] (* Wesley Ivan Hurt, Apr 16 2014 *)
PROG
(PARI) a(n)=n%3+(n%3==2) \\ Jaume Oliver Lafont, Mar 24 2009
(PARI) a(n)=2^(n%3)-1 \\ Jaume Oliver Lafont, Mar 24 2009
CROSSREFS
Sequence in context: A014513 A144388 A133513 * A035653 A126595 A286096
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jun 17 2007
STATUS
approved