|
| |
|
|
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; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| From Balmer spectrum of hydrogen.
Terms of the simple continued fraction of 2/[sqrt(70)-8]. Decimal expansion of 478/909. [From Paolo P. Lava (paoloplava(AT)gmail.com), Aug 05 2009]
|
|
|
LINKS
| Index to sequences with linear recurrences with constant coefficients, signature (1,-1,1)
|
|
|
FORMULA
| a(n)=(1/12)*{19*(n mod 4)+[(n+1) mod 4]+[(n+2) mod 4]+19*[(n+3) mod 4]}, with n>=0 [From Paolo P. Lava (paoloplava(AT)gmail.com), Sep 29 2008]
a(n)=5+(3/2)*I*I^n-(3/2)*I*(-I)^n, with n>=0 and I=sqrt(-1) [From Paolo P. Lava (paoloplava(AT)gmail.com), Sep 16 2009]
G.f. ( -5+3*x-8*x^2 ) / ( (x-1)*(1+x^2) ). - R. J. Mathar, Apr 02 2011
|
|
|
PROG
| (PARI) a(n)=5+3*cos(n*Pi/2) [From Jaume Oliver Lafont (joliverlafont(AT)gmail.com), Aug 30 2009]
|
|
|
CROSSREFS
| Sequence in context: A082571 A087300 A074455 * A201530 A085997 A071546
Adjacent sequences: A142699 A142700 A142701 * A142703 A142704 A142705
|
|
|
KEYWORD
| nonn,easy
|
|
|
AUTHOR
| Paul Curtz (bpcrtz(AT)free.fr), Sep 23 2008
|
|
|
EXTENSIONS
| Edited by N. J. A. Sloane (njas(AT)research.att.com), Sep 27 2008
|
| |
|
|
