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A130794
Periodic sequence with period 1,5,3.
4
1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1, 5, 3, 1
OFFSET
0,2
COMMENTS
Continued fraction expansion of (7+sqrt(145))/16. - Klaus Brockhaus, Apr 28 2010
Decimal expansion of 17/111. - R. J. Mathar, Aug 05 2013
This is also the periodic unsigned Schick sequence for 7. See the Schick reference, p. 158 for p = 7 (the row labels should there be q_j, j >= 0). - Wolfdieter Lang, Apr 03 2020
REFERENCES
Carl Schick, Trigonometrie und unterhaltsame Zahlentheorie, Bokos Druck, Zürich, 2003 (ISBN 3-9522917-0-6). Tables 3.1 to 3.10, for odd p = 3..113 (with gaps), pp. 158-166. Here p = 7.
FORMULA
G.f.: ( -1-5*x-3*x^2 ) / ( (x-1)*(1+x+x^2) ). - R. J. Mathar, Aug 05 2013
a(n) = 5 - 2 * mod(n+2,3). - Wesley Ivan Hurt, Mar 15 2014
MAPLE
A130794:=n->5 - 2 * ((n+2) mod 3); seq(A130794(n), n=0..100); # Wesley Ivan Hurt, Mar 15 2014
MATHEMATICA
Table[5 - 2 Mod[n + 2, 3], {n, 0, 100}] (* Wesley Ivan Hurt, Mar 15 2014 *)
PadRight[{}, 120, {1, 5, 3}] (* Harvey P. Dale, Jun 15 2019 *)
PROG
(PARI) a(n)=[1, 5, 3][n%3+1] \\ Charles R Greathouse IV, Jun 02 2011
CROSSREFS
Cf. A176908 (decimal expansion of (7+sqrt(145))/16). - Klaus Brockhaus, Apr 28 2010
Sequence in context: A154180 A011332 A092235 * A242908 A023578 A111487
KEYWORD
nonn,easy,less
AUTHOR
Paul Curtz, Jul 15 2007
STATUS
approved