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%I #13 Sep 08 2022 08:44:57
%S 1,6,21,61,161,401,961,2241,5121,11521,25601,56321,122881,266241,
%T 573441,1228801,2621441,5570561,11796481,24903681,52428801,110100481,
%U 230686721,482344961,1006632961,2097152001,4362076161,9059696641,18790481921,38923141121
%N a(n) = T(4,n), array T given by A048472.
%C n-th difference of a(n), a(n-1), ..., a(0) is (5, 10, 15, ...).
%H Vincenzo Librandi, <a href="/A048476/b048476.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (5,-8,4).
%F a(n) = 5*n * 2^(n-1) + 1.
%F a(n) = 5*a(n-1)-8*a(n-2)+4*a(n-3) for n>2. G.f.: (1+x-x^2) / ((1-x)*(1-2*x)^2). - _Colin Barker_, Feb 18 2016
%o (Magma) [5*n * 2^(n-1) + 1: n in [0..30]]; // _Vincenzo Librandi_, Sep 23 2011
%o (PARI) Vec((1+x-x^2)/((1-x)*(1-2*x)^2) + O(x^40)) \\ _Colin Barker_, Feb 18 2016
%K nonn,easy
%O 0,2
%A _Clark Kimberling_
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