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A024078 a(n) = 7^n - n^3. 2

%I

%S 1,6,41,316,2337,16682,117433,823200,5764289,40352878,282474249,

%T 1977325412,13841285473,96889008210,678223070105,4747561506568,

%U 33232930565505,232630513982294,1628413597904617,11398895185366284,79792266297604001,558545864083274746

%N a(n) = 7^n - n^3.

%H Vincenzo Librandi, <a href="/A024078/b024078.txt">Table of n, a(n) for n = 0..500</a>

%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (11,-34,46,-29,7).

%F From _Colin Barker_, Oct 05 2018: (Start)

%F G.f.: (1 + x)*(1 - 6*x + 15*x^2 + 8*x^3) / ((1 - x)^4*(1 - 7*x)).

%F a(n) = 11*a(n-1) - 34*a(n-2) + 46*a(n-3) - 29*a(n-4) + 7*a(n-5) for n>4.

%F (End)

%o (MAGMA) [7^n-n^3: n in [0..25]]; // _Vincenzo Librandi_, Jul 03 2011

%o (PARI) Vec((1 + x)*(1 - 6*x + 15*x^2 + 8*x^3) / ((1 - x)^4*(1 - 7*x)) + O(x^30)) \\ _Colin Barker_, Oct 05 2018

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_

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Last modified January 25 08:36 EST 2022. Contains 350565 sequences. (Running on oeis4.)