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a(n) = 9^n-n^7.
2

%I #21 Sep 08 2022 08:44:48

%S 1,8,-47,-1458,-9823,-19076,251505,3959426,40949569,382637520,

%T 3476784401,31361572438,282393704673,2541803079812,22876687041457,

%U 205890961235274,1853019920416385,16677181289327896,150094634684779089,1350851716779120350

%N a(n) = 9^n-n^7.

%H Vincenzo Librandi, <a href="/A024108/b024108.txt">Table of n, a(n) for n = 0..400</a>

%H <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (17,-100,308,-574,686,-532,260,-73,9).

%F G.f.: -(10*x^8+1071*x^7+10627*x^6+20497*x^5+8373*x^4-167*x^3-83*x^2-9*x+1) / ((x-1)^8*(9*x-1)). - _Colin Barker_, Mar 20 2015

%F a(n) = A001019(n) - A001015(n). - _Michel Marcus_, Mar 20 2015

%t Table[9^n - n^7, {n, 0, 19}] (* _Michael De Vlieger_, Mar 20 2015 *)

%t LinearRecurrence[{17,-100,308,-574,686,-532,260,-73,9},{1,8,-47,-1458,-9823,-19076,251505,3959426,40949569},20] (* _Harvey P. Dale_, Mar 23 2018 *)

%o (Magma) [9^n-n^7: n in [0..25]]; // _Vincenzo Librandi_, Jul 06 2011

%o (PARI) Vec(-(10*x^8+1071*x^7+10627*x^6+20497*x^5+8373*x^4-167*x^3-83*x^2-9*x+1)/((x-1)^8*(9*x-1)) + O(x^100)) \\ _Colin Barker_, Mar 20 2015

%K sign,easy

%O 0,2

%A _N. J. A. Sloane_