login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A166592 Hankel transform of A166588(n-1). 2
0, 1, 3, 2, 3, 1, 0, -1, -3, -2, -3, -1, 0, 1, 3, 2, 3, 1, 0, -1, -3, -2, -3, -1, 0, 1, 3, 2, 3, 1, 0, -1, -3, -2, -3, -1, 0, 1, 3, 2, 3, 1, 0, -1, -3, -2, -3, -1, 0, 1, 3, 2, 3, 1, 0, -1, -3, -2, -3, -1, 0, 1, 3, 2, 3, 1, 0, -1, -3, -2, -3, -1, 0, 1, 3, 2, 3, 1, 0, -1, -3, -2, -3, -1, 0, 1, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
Hankel transform of 0,1,2,2,3,3,5,5,10,10,... is -a(n).
LINKS
FORMULA
G.f.: x(1+3x+x^2)/(1-x^2+x^4).
a(n) = (1-sqrt(3))*sin(5*Pi*n/6)+(1+sqrt(3))*sin(Pi*n/6).
From G. C. Greubel, May 18 2016: (Start)
a(n+12) = a(n).
a(n) = a(n-2) - a(n-4). (End)
E.g.f.: 2*sin(x/2)*(sqrt(3)*sinh(sqrt(3)*x/2) + cosh(sqrt(3)*x/2)). - Ilya Gutkovskiy, May 18 2016
MATHEMATICA
CoefficientList[Series[x (1 + 3 x + x^2)/(1 - x^2 + x^4), {x, 0, 10}], x] (* or *) LinearRecurrence[{0, 1, 0, -1}, {0, 1, 3, 2}, 25] (* G. C. Greubel, May 18 2016 *)
CROSSREFS
Sequence in context: A086099 A048967 A324182 * A103497 A191390 A309698
KEYWORD
easy,sign
AUTHOR
Paul Barry, Oct 17 2009
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 29 05:48 EDT 2024. Contains 371265 sequences. (Running on oeis4.)