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a(n) = T(7,n), array T given by A047858.
1

%I #17 Sep 08 2022 08:44:57

%S 1,9,26,62,138,298,634,1338,2810,5882,12282,25594,53242,110586,229370,

%T 475130,983034,2031610,4194298,8650746,17825786,36700154,75497466,

%U 155189242,318767098,654311418,1342177274,2751463418,5637144570,11542724602,23622320122

%N a(n) = T(7,n), array T given by A047858.

%C n-th difference of a(n), a(n-1), ..., a(0) is (8, 9, 10, ...).

%H Vincenzo Librandi, <a href="/A048468/b048468.txt">Table of n, a(n) for n = 0..3000</a>

%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (5, -8, 4).

%F a(n) = 2^(n-1)*(n+14)-6. a(0)=1, a(1)=9, a(2)=26, a(n) = 5*a(n-1)-8*a(n-2)+4*a(n-3). - _Vincenzo Librandi_, Sep 28 2011

%F a(n) = 2^(n-1)*(n+14)-6. G.f.: (1+4*x-11*x^2) / ((1-x)*(1-2*x)^2). - _Colin Barker_, Feb 18 2016

%t LinearRecurrence[{5,-8,4},{1,9,26},30] (* _Harvey P. Dale_, Apr 19 2012 *)

%o (Magma) [2^(n-1)*(n+14)-6: n in [0..30]]; // _Vincenzo Librandi_, Sep 28 2011

%o (PARI) Vec((1+4*x-11*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_