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a(n) = T(2*n, n+3), T given by A027935.
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%I #15 Sep 08 2022 08:44:49

%S 1,29,247,1300,5270,18228,56967,166681,467301,1274856,3419252,9076280,

%T 23945893,62955061,165188091,432974764,1134224458,2970340412,

%U 7777628427,20363608737,53314542953,139581703056,365432651464,956718812272,2504726904937,6557465674125

%N a(n) = T(2*n, n+3), T given by A027935.

%H G. C. Greubel, <a href="/A027939/b027939.txt">Table of n, a(n) for n = 3..1000</a>

%H <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (9,-34,71,-90,71,-34,9,-1).

%F G.f.: x^3*(1+20*x+20*x^2-8*x^3-x^4) / ((1-x)^6*(1-3*x+x^2)). - _Colin Barker_, Feb 20 2016

%F a(n) = Fibonacci(2*n+7) - (195 + 186*n + 90*n^2 + 35*n^3 + 4*n^5)/15. - _G. C. Greubel_, Sep 28 2019

%p with(combinat); seq(fibonacci(2*n+7) - (195 +186*n +90*n^2 +35*n^3 +4*n^5)/15, n=3..30); # _G. C. Greubel_, Sep 28 2019

%t Table[Fibonacci[2*n+7] -(195 +186*n +90*n^2 +35*n^3 +4*n^5)/15, {n,3,30}] (* _G. C. Greubel_, Sep 28 2019 *)

%o (PARI) vector(30, n, my(m=n+2); fibonacci(2*m+7) - (195 +186*m +90*m^2 +35*m^3 +4*m^5)/15) \\ _G. C. Greubel_, Sep 28 2019

%o (Magma) [Fibonacci(2*n+7) - (195 +186*n +90*n^2 +35*n^3 +4*n^5)/15: n in [3..30]]; // _G. C. Greubel_, Sep 28 2019

%o (Sage) [fibonacci(2*n+7) - (195 +186*n +90*n^2 +35*n^3 +4*n^5)/15 for n in (3..30)] # _G. C. Greubel_, Sep 28 2019

%o (GAP) List([3..30], n-> Fibonacci(2*n+7) - (195 +186*n +90*n^2 +35*n^3 +4*n^5)/15 ); # _G. C. Greubel_, Sep 28 2019

%Y Cf. A000045, A027935.

%K nonn

%O 3,2

%A _Clark Kimberling_

%E Terms a(23) onward added by _G. C. Greubel_, Sep 28 2019