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A142702 Period 4: repeat [5, 2, 5, 8]. 0
5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8, 5, 2, 5, 8 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
From Balmer spectrum of hydrogen.
LINKS
FORMULA
a(n) = 5+3*cos(n*Pi/2). [From PARI program of Lafont, Aug 30 2009].
G.f.: ( 5-3*x+8*x^2 ) / ( (1-x)*(1+x^2) ). - R. J. Mathar, Apr 02 2011
a(n) = a(n-1) - a(n-2) + a(n-3) for n>3. - Wesley Ivan Hurt, Jul 08 2016
MAPLE
seq(op([5, 2, 5, 8]), n=1..50); # Wesley Ivan Hurt, Jul 08 2016
MATHEMATICA
PadRight[{}, 100, {5, 2, 5, 8}] (* Harvey P. Dale, Dec 09 2013 *)
PROG
(PARI) a(n)=5+3*cos(n*Pi/2) \\ [Jaume Oliver Lafont, Aug 30 2009]
(Magma) &cat [[5, 2, 5, 8]^^30]; // Wesley Ivan Hurt, Jul 08 2016
CROSSREFS
Sequence in context: A087300 A074455 A339161 * A236184 A201530 A085997
KEYWORD
nonn,easy
AUTHOR
Paul Curtz, Sep 23 2008
EXTENSIONS
Edited by N. J. A. Sloane, Sep 27 2008
STATUS
approved

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Last modified June 19 09:37 EDT 2024. Contains 373501 sequences. (Running on oeis4.)