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A138233 2^(2*n+1) + 3^(2*n+1). 1
5, 35, 275, 2315, 20195, 179195, 1602515, 14381675, 129271235, 1162785755, 10462450355, 94151567435, 847322163875, 7625731702715, 68630914235795, 617675543767595, 5559069156490115, 50031579458738075, 450284043329950835 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Subsequence of A008587; A096951(n) = a(n)/5.

LINKS

Table of n, a(n) for n=0..18.

Index entries for linear recurrences with constant coefficients, signature (13, -36).

FORMULA

a(n+1) = 4*a(n) + 5*3^(2*n+1), a(0) = 5.

O.g.f.: -5x(-7+36x)/((-1+4x)(-1+9x)). - R. J. Mathar, Apr 24 2008

MATHEMATICA

LinearRecurrence[{13, -36}, {5, 35}, 19] (* Ray Chandler, Jul 14 2017 *)

2^#+3^#&/@(2*Range[0, 20]+1) (* Harvey P. Dale, Sep 25 2019 *)

CROSSREFS

Cf. A138199.

Sequence in context: A087630 A084135 A229111 * A322666 A248053 A002294

Adjacent sequences:  A138230 A138231 A138232 * A138234 A138235 A138236

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Mar 07 2008

STATUS

approved

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Last modified December 12 22:06 EST 2019. Contains 329963 sequences. (Running on oeis4.)