login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A049672 a(n) = (F(4*n) - F(n))/2, where F=A000045 (the Fibonacci sequence). 1
0, 1, 10, 71, 492, 3380, 23180, 158899, 1089144, 7465159, 51167050, 350704322, 2403763416, 16475639933, 112925716670, 774004377655, 5305104928368, 36361730123272, 249227005938340, 1708227311451263 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (8,-7,-6,1).

FORMULA

G.f.: x*(-1-2*x+2*x^2) / ( (x^2+x-1)*(x^2-7*x+1) ). - R. J. Mathar, Oct 26 2015

MATHEMATICA

LinearRecurrence[{8, -7, -6, 1}, {0, 1, 10, 71}, 50] (* or *) Table[(1/2) *(Fibonacci[4*n] - Fibonacci[n]), {n, 0, 30}] (* G. C. Greubel, Dec 02 2017 *)

PROG

(PARI) for(n=0, 30, print1((fibonacci(4*n) - fibonacci(n))/2, ", ")) \\ G. C. Greubel, Dec 02 2017

(MAGMA) [(Fibonacci(4*n) - Fibonacci(n))/2: n in [0..30]]; // G. C. Greubel, Dec 02 2017

CROSSREFS

Sequence in context: A224292 A016098 A129275 * A221548 A037579 A166791

Adjacent sequences:  A049669 A049670 A049671 * A049673 A049674 A049675

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy .

Last modified February 19 10:40 EST 2018. Contains 299330 sequences. (Running on oeis4.)