A131712 Period 4: repeat [1, 3, 7, 9].
1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1, 3, 7, 9, 1
Offset: 0
Links
- Index entries for linear recurrences with constant coefficients, signature (0,0,0,1).
Crossrefs
Cf. A178148 (decimal expansion of (243+17*sqrt(285))/402). - Klaus Brockhaus, May 21 2010
Programs
-
Magma
&cat[[1, 3, 7, 9]: k in [1..30]]; // Vincenzo Librandi, Nov 23 2010
-
Maple
seq(op([1, 3, 7, 9]), n=0..40); # Wesley Ivan Hurt, Jul 09 2016
-
Mathematica
PadRight[{}, 100, {1, 3, 7, 9}] (* Wesley Ivan Hurt, Jul 09 2016 *) -
PARI
a(n)=1+2*(n%4)+2*(n%4\2) \\ Jaume Oliver Lafont, Aug 28 2009
Formula
G.f.: (1+3*x+7*x^2+9*x^3)/((1-x)*(x+1)*(1+x^2)). - R. J. Mathar, Nov 14 2007
From Wesley Ivan Hurt, Jul 09 2016: (Start)
a(n) = a(n-4) for n>3.
a(n) = 5 - 3*cos(n*Pi/2) - cos(n*Pi) - 3*sin(n*Pi/2) - I*sin(n*Pi). (End)
Extensions
More terms from Klaus Brockhaus, May 21 2010
Comments