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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A200408 -4 + 5*Fibonacci(n+1)^2. 0
1, 16, 41, 121, 316, 841, 2201, 5776, 15121, 39601, 103676, 271441, 710641, 1860496, 4870841, 12752041, 33385276, 87403801, 228826121, 599074576, 1568397601, 4106118241, 10749957116, 28143753121, 73681302241, 192900153616, 505019158601, 1322157322201 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(1) and a(2n) are perfect squares.

LINKS

Table of n, a(n) for n=1..28.

Index entries for linear recurrences with constant coefficients, signature (3,0,-3,1).

FORMULA

a(n) = 3*a(n-1)-3*a(n-3)+a(n-4). G.f.: -x*(x^3-7*x^2+13*x+1) / ((x-1)*(x+1)*(x^2-3*x+1)). - Colin Barker, Sep 01 2013

MATHEMATICA

Table[-4 + 5*Fibonacci[n]^2, {n, 2, 31}] (* Alonso del Arte, Nov 17 2011 *)

PROG

(PARI) Vec(-x*(x^3-7*x^2+13*x+1)/((x-1)*(x+1)*(x^2-3*x+1)) + O(x^100)) \\ Colin Barker, Sep 01 2013

CROSSREFS

Cf. A000045.

Sequence in context: A188861 A134593 A227816 * A280184 A228685 A317761

Adjacent sequences:  A200405 A200406 A200407 * A200409 A200410 A200411

KEYWORD

nonn,easy

AUTHOR

Artur Jasinski, Nov 17 2011

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 21 15:32 EDT 2019. Contains 323444 sequences. (Running on oeis4.)