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T(n,n-6), where T is the array in A055830.
2

%I #16 Sep 08 2022 08:45:01

%S 13,58,162,361,701,1239,2044,3198,4797,6952,9790,13455,18109,23933,

%T 31128,39916,50541,63270,78394,96229,117117,141427,169556,201930,

%U 239005,281268,329238,383467,444541,513081

%N T(n,n-6), where T is the array in A055830.

%H G. C. Greubel, <a href="/A055833/b055833.txt">Table of n, a(n) for n = 6..1000</a>

%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (6,-15,20,-15,6,-1).

%F From _R. J. Mathar_, Mar 13 2016: (Start)

%F G.f.: x^6*(13 -20*x +9*x^2 -x^3)/(1-x)^6.

%F a(n) = (n-5)*(n-4)*(n^3 +19*n^2 +6*n -156)/120. (End)

%F E.g.f.: (3120 + 1560*x + 180*x^2 - 20*x^3 - (3120 - 1560*x + 180*x^2 + 60*x^3 - 20*x^4 - x^5)*exp(x))/120. - _G. C. Greubel_, Jan 21 2020

%p seq( (n-5)*(n-4)*(n^3 +19*n^2 +6*n -156)/120, n=6..40); # _G. C. Greubel_, Jan 21 2020

%t Table[(n-5)*(n-4)*(n^3 +19*n^2 +6*n -156)/120, {n,6,40}] (* _G. C. Greubel_, Jan 21 2020 *)

%o (PARI) a(n) = (n-5)*(n-4)*(n^3 +19*n^2 +6*n -156)/120; \\ _G. C. Greubel_, Jan 21 2020

%o (Magma) [(n-5)*(n-4)*(n^3 +19*n^2 +6*n -156)/120: n in [6..40]]; // _G. C. Greubel_, Jan 21 2020

%o (Sage) [(n-5)*(n-4)*(n^3 +19*n^2 +6*n -156)/120 for n in (6..40)] # _G. C. Greubel_, Jan 21 2020

%o (GAP) List([6..40], n-> (n-5)*(n-4)*(n^3 +19*n^2 +6*n -156)/120 ); # _G. C. Greubel_, Jan 21 2020

%Y Cf. A055830.

%K nonn,easy

%O 6,1

%A _Clark Kimberling_, May 28 2000