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n*Jacobsthal(n).
1

%I #10 May 07 2019 11:12:04

%S 0,1,2,9,20,55,126,301,680,1539,3410,7513,16380,35503,76454,163845,

%T 349520,742747,1572858,3320497,6990500,14680071,30758222,64312669,

%U 134217720,279620275,581610146,1207959561,2505397580,5189752159

%N n*Jacobsthal(n).

%C Convolution of Jacobsthal numbers A001045 and modified Jacobsthal-Lucas numbers (in A014551, change the leading 2 to a 1).

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (2,3,-4,-4).

%F G.f.: x(1+2x^2)/(1-x-2x^2)^2; a(n)=n2^n/3-n(-1)^n/3.

%F a(n) = n*A001045(n). - _R. J. Mathar_, May 07 2019

%t LinearRecurrence[{2,3,-4,-4},{0,1,2,9},30] (* _Harvey P. Dale_, Jun 17 2017 *)

%Y Cf. A023607.

%K nonn,easy

%O 0,3

%A _Paul Barry_, Apr 20 2004