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Revision History for A117110

(Underlined text is an addition; strikethrough text is a deletion.)

Showing entries 1-10 | older changes
A117110 Expansion of x*(1+5*x)/((1+2*x+1)*(1-4*x)).
(history; published version)
#14 by Joerg Arndt at Mon Jan 01 11:42:14 EST 2024
STATUS

editing

approved

#13 by Joerg Arndt at Mon Jan 01 11:42:09 EST 2024
NAME

The (1,1)-entry of the vector v[n]=Mv[n-1], where M is the 3 x 3 matrix [[0,-1/r,r],[ -1/r,-2/r,1],[r,1,2+2/r]], r being the golden ratio and v[0] is the column matrix [0,1,1].

Expansion of x*(1+5*x)/((1+2*x+1)*(1-4*x)).

COMMENTS

Characteristic polynomial of the matrix M is x(x^2-2x-8).

FORMULA

Recurrence relation: a(n)=2a) = 2*a(n-1)+8a) + 8*a(n-2) for n>=3; a(0)=0,, a(1)=1,, a(2)=7.

O.g.f.: -.: x*(1+5*x)/((1+2*x+1)*(1-4*x-1)). - R. J. Mathar, Dec 05 2007

MAPLE

with(linalg): r:=(1+sqrt(5))/2: M:=matrix(3, 3, [0, -1/r, r, -1/r, -2/r, 1, r, 1, 2+2/r]): v[0]:=matrix(3, 1, [0, 1, 1]): for n from 1 to 26 do v[n]:=simplify(multiply(M, v[n-1])) od: seq(simplify(rationalize(v[n][1, 1])), n=0..26);

KEYWORD

nonn,easy,changed

EXTENSIONS

New name using g.f. from Joerg Arndt, Jan 01 2024

STATUS

approved

editing

#12 by Joerg Arndt at Mon Jan 01 11:40:34 EST 2024
STATUS

editing

approved

#11 by Paolo P. Lava at Mon Jan 01 11:39:57 EST 2024
FORMULA

a(n)=-(1/2)*(-2)^(n-1)+(3/2)*4^(n-1)-5/8*[C(2*n,n) mod 2], with n>=0 [From Paolo P. Lava, Oct 07 2008]

STATUS

approved

editing

#10 by Russ Cox at Fri Mar 30 18:53:35 EDT 2012
FORMULA

a(n)=-(1/2)*(-2)^(n-1)+(3/2)*4^(n-1)-5/8*[C(2*n,n) mod 2], with n>=0 [From _Paolo P. Lava (paoloplava(AT)gmail.com), _, Oct 07 2008]

Discussion
Fri Mar 30 18:53
OEIS Server: https://oeis.org/edit/global/262
#9 by Russ Cox at Fri Mar 30 17:39:11 EDT 2012
FORMULA

O.g.f.: -x*(1+5*x)/((2*x+1)*(4*x-1)). - )). - _R. J. Mathar (mathar(AT)strw.leidenuniv.nl), _, Dec 05 2007

Discussion
Fri Mar 30 17:39
OEIS Server: https://oeis.org/edit/global/190
#8 by Russ Cox at Fri Mar 30 17:34:20 EDT 2012
AUTHOR

_Roger L. Bagula (rlbagulatftn(AT)yahoo.com), _, Apr 18 2006

Discussion
Fri Mar 30 17:34
OEIS Server: https://oeis.org/edit/global/158
#7 by Russ Cox at Fri Mar 30 16:50:24 EDT 2012
EXTENSIONS

Edited by _N. J. A. Sloane (njas(AT)research.att.com), _, May 13 2006

Discussion
Fri Mar 30 16:50
OEIS Server: https://oeis.org/edit/global/110
#6 by T. D. Noe at Wed Sep 28 20:48:35 EDT 2011
FORMULA

a(n)=-(1/2)*(-2)^(n-1)+(3/2)*4^(n-1)-5/8*[C(2*n,n) mod 2], with n>=0 [From Paolo P. Lava (pplpaoloplava(AT)splgmail.atcom), Oct 07 2008]

Discussion
Wed Sep 28 20:48
OEIS Server: https://oeis.org/edit/global/96
#5 by N. J. A. Sloane at Fri Feb 27 03:00:00 EST 2009
NAME

The (1,1)-entry of the vector v[n]=Mv[n-1], where M is the 3 x 3 matrix [[0,-1/r,r],[ -1/r,-2/r,1],[r,1,2+2/r]], r being the golden ratio, and v[0] is the column matrix [0,1,1].

KEYWORD

nonn,new

nonn

EXTENSIONS

Edited by N. J. A. Sloane (njas, (AT)research.att.com), May 13 2006

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Last modified August 18 18:17 EDT 2024. Contains 375273 sequences. (Running on oeis4.)