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A024090 8^n-n^2. 2

%I

%S 1,7,60,503,4080,32743,262108,2097103,16777152,134217647,1073741724,

%T 8589934471,68719476592,549755813719,4398046510908,35184372088607,

%U 281474976710400,2251799813684959,18014398509481660

%N 8^n-n^2.

%H Vincenzo Librandi, <a href="/A024090/b024090.txt">Table of n, a(n) for n = 0..400</a>

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (11,-27,25,-8).

%F G.f.: (1-4*x+10*x^2+7*x^3)/((1-8*x)*(1-x)^3). - _Vincenzo Librandi_, Oct 06 2014

%F a(n) = 11*a(n-1) -27*a(n-2) +25*a(n-3) -8*a(n-4) for n>3. - _Vincenzo Librandi_, Oct 06 2014

%F a(n) = A001018(n) - A000290(n). - _Michel Marcus_, Oct 06 2014

%t Table[8^n - n^2, {n, 0, 25}] (* or *) CoefficientList[Series[(1 - 4 x + 10 x^2 + 7 x^3)/((1 - 8 x) (1 - x)^3), {x, 0, 30}], x] (* _Vincenzo Librandi_, Oct 06 2014 *)

%o (MAGMA) [8^n-n^2: n in [0..20]]; // _Vincenzo Librandi_, Jul 05 2011

%Y Cf. similar sequences listed in A024025.

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_.

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Last modified June 23 21:09 EDT 2021. Contains 345402 sequences. (Running on oeis4.)