

A167710


a(n) = 10*2^n  3*A083658(n+2).


2



1, 5, 13, 35, 79, 185, 397, 875, 1831, 3905, 8053, 16835, 34399, 70985, 144157, 294875, 596311, 1212305, 2444293, 4947635, 9954319, 20085785, 40348717, 81228875, 162989191, 327572705, 656739733, 1318262435, 2641307839, 5296964585, 10608278077, 21259602875
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OFFSET

0,2


COMMENTS

The sequence can be defined as the row sums of the triangle T(n,k)
.1;
.3,.2;
.3,.6,.4;
.9,.6,12,.8;
.9,18,12,24,16;
27,18,36,24,48,32;
with left column A162436, diagonal the powers of 2, and the recurrence T(n+2,k) = 3*T(n,k).


LINKS

G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (2,3,6).


FORMULA

a(n+1)  2*a(n) = A162436(n+2).
a(n) = 2*a(n1) + 3*a(n2)  6*a(n3).
G.f.: (1+3*x)/((2*x1) * (3*x^21)).  R. J. Mathar, Feb 27 2010


MATHEMATICA

LinearRecurrence[{2, 3, 6}, {1, 5, 13}, 40] (* Harvey P. Dale, Oct 03 2014 *)


CROSSREFS

Sequence in context: A006561 A146845 A192310 * A229924 A264080 A290588
Adjacent sequences: A167707 A167708 A167709 * A167711 A167712 A167713


KEYWORD

nonn,easy


AUTHOR

Paul Curtz, Nov 10 2009


EXTENSIONS

Replaced crossreferences by link to the index  R. J. Mathar, Feb 27 2010


STATUS

approved



