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A010717
Period 2: repeat (5,6).
3
5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5, 6, 5
OFFSET
0,1
COMMENTS
This is the continued fraction expansion of the constant A176320 = 5/2 + sqrt(255)/6. - R. J. Mathar, Nov 21 2011
FORMULA
From Vincenzo Librandi, Aug 01 2010: (Start)
a(n) = a(n-2) for n>1; a(0)=5, a(1)=6.
G.f.: (5+6*x)/((1-x)*(1+x)). (End)
a(n) = floor(11*(n+1)/2) - floor(11*n/2). - James Van Alstine, Jul 17 2014
MAPLE
A010717:= n -> 5 + (n mod 2):
seq(A010717(n), n=0..10); # Robert Israel, Jul 17 2014
MATHEMATICA
Table[5 + Mod[n, 2], {n, 0, 50}] (* Jinyuan Wang, Feb 26 2020 *)
PROG
(PARI) contfrac(5/2+sqrt(precision(255., 150))/6) \\ Note: Depending on the chosen precision, the last term may be off by +/- 1, so it would be safer to discard it, e.g., using vecextract(..., "^-1"). - M. F. Hasler, Sep 25 2013
(PARI) a(n)=n%2+5 \\ Charles R Greathouse IV, Jul 13 2016
CROSSREFS
Sequence in context: A106704 A127205 A006944 * A046603 A139396 A010487
KEYWORD
nonn,easy
STATUS
approved