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Revision History for A179991

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Showing entries 1-10 | older changes
A179991 Nonhomogeneous three-term sequence a(n) = a(n-1) + a(n-2) + n.
(history; published version)
#17 by Michel Marcus at Sun Mar 12 08:37:22 EDT 2017
STATUS

reviewed

approved

#16 by Joerg Arndt at Sun Mar 12 07:55:35 EDT 2017
STATUS

proposed

reviewed

#15 by Colin Barker at Sun Mar 12 06:26:43 EDT 2017
STATUS

editing

proposed

#14 by Colin Barker at Sun Mar 12 06:26:29 EDT 2017
PROG

(PARI) Vec(x*(x-2)*(x^2-x+1) / ((x^2+x-1)*(x-1)^2) + O(x^50)) \\ Colin Barker, Mar 12 2017

#13 by Colin Barker at Sun Mar 12 06:25:40 EDT 2017
NAME

Nonhomogeneous three-term sequence a(n) = a(n-1)+) + a(n-2)+) + n.

DATA

2, 3, 8, 15, 28, 49, 84, 141, 234, 385, 630, 1027, 1670, 2711, 4396, 7123, 11536, 18677, 30232, 48929, 79182, 128133, 207338, 335495, 542858, 878379, 1421264, 2299671, 3720964, 6020665, 9741660, 15762357, 25504050, 41266441, 66770526, 108037003, 174807566

LINKS

Colin Barker, <a href="/A179991/b179991.txt">Table of n, a(n) for n = 1..1000</a>

FORMULA

G.Ff.: x*(x-2)*(x^2-x+1) / ( (x^2+x-1)*(x-1)^2 ).

From Colin Barker, Mar 12 2017: (Start)

a(n) = 2^(-n)*(-3*2^n+(1-sqrt(5))^(1+n) + (1+sqrt(5))^n + sqrt(5)*(1+sqrt(5))^n - 2^n*n).

a(n) = 3*a(n-1) - 2*a(n-2) - a(n-3) + a(n-4) for n>4.

(End)

STATUS

approved

editing

#12 by Charles R Greathouse IV at Sat Jun 13 00:53:39 EDT 2015
LINKS

<a href="/index/Rec#order_04">Index to sequencesentries withfor linear recurrences with constant coefficients</a>, signature (3,-2,-1,1).

Discussion
Sat Jun 13 00:53
OEIS Server: https://oeis.org/edit/global/2439
#11 by R. J. Mathar at Sun May 04 15:57:49 EDT 2014
STATUS

editing

approved

#10 by R. J. Mathar at Sun May 04 15:54:19 EDT 2014
CROSSREFS

Cf. A000045., A022319 (first differences).

KEYWORD

nonn,easy,changed

STATUS

proposed

editing

#9 by R. J. Mathar at Sun May 04 15:49:59 EDT 2014
STATUS

editing

proposed

#8 by R. J. Mathar at Sun May 04 15:49:34 EDT 2014
LINKS

<a href="/index/Rec#order_04">Index to sequences with linear recurrences with constant coefficients</a>, signature (3,-2,-1,1).

FORMULA

G.F.: x*(x^3-3*x^2+3*x-2)/()*(x^42-x^3-2*+1) / ( (x^2+3*x-1)*(x-1).)^2 ).

EXTENSIONS

G.f. multiplied by x. - R. J. Mathar, Aug 09 2010

STATUS

approved

editing

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Last modified September 12 07:57 EDT 2024. Contains 375850 sequences. (Running on oeis4.)