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a(n) = T(2*n, n+4), T given by A027935.
1

%I #13 Sep 08 2022 08:44:49

%S 1,46,551,3785,18955,77533,276408,895103,2708322,7811510,21791338,

%T 59419294,159571139,424302452,1121168305,2951121095,7749900701,

%U 20324325571,53259796514,139506540045,365330860180,956582678652,2504546934692,6557230277964,17167369784405

%N a(n) = T(2*n, n+4), T given by A027935.

%H G. C. Greubel, <a href="/A027940/b027940.txt">Table of n, a(n) for n = 4..1000</a>

%H <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (11,-53,148,-266,322,-266,148,-53,11,-1).

%F From _G. C. Greubel_, Sep 28 2019: (Start)

%F a(n) = Fibonacci(2*n+9) - (21420 + 20571*n + 9961*n^2 + 3304*n^3 + 490*n^4 + 364*n^5 - 56*n^6 + 16*n^7)/630.

%F G.f.: x^4*(1 + 35*x + 98*x^2 + 14*x^3 - 19*x^4 - x^5)/((1-x)^8*(1 - 3*x + x^2)). (End)

%p with(combinat); seq(fibonacci(2*n+9) - (21420 +20571*n +9961*n^2 +3304*n^3 +490*n^4 +364*n^5 -56*n^6 +16*n^7)/630, n=4..40); # _G. C. Greubel_, Sep 28 2019

%t Table[Fibonacci[2*n+9] - (21420 +20571*n +9961*n^2 +3304*n^3 +490*n^4 +364*n^5 -56*n^6 +16*n^7)/630, {n,4,40}] (* _G. C. Greubel_, Sep 28 2019 *)

%o (PARI) vector(40, n, my(m=n+3); fibonacci(2*m+9) - (21420 +20571*m +9961*m^2 +3304*m^3 +490*m^4 +364*m^5 -56*m^6 +16*m^7)/630) \\ _G. C. Greubel_, Sep 28 2019

%o (Magma) [Fibonacci(2*n+9) - (21420 +20571*n +9961*n^2 +3304*n^3 +490*n^4 +364*n^5 -56*n^6 +16*n^7)/630: n in [4..40]]; // _G. C. Greubel_, Sep 28 2019

%o (Sage) [fibonacci(2*n+9) - (21420 +20571*n +9961*n^2 +3304*n^3 +490*n^4 +364*n^5 -56*n^6 +16*n^7)/630 for n in (4..40)] # _G. C. Greubel_, Sep 28 2019

%o (GAP) List([4..40], n-> Fibonacci(2*n+9) - (21420 +20571*n +9961*n^2 +3304*n^3 +490*n^4 +364*n^5 -56*n^6 +16*n^7)/630 ); # _G. C. Greubel_, Sep 28 2019

%Y Cf. A000045, A027935.

%K nonn,easy

%O 4,2

%A _Clark Kimberling_

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