A017186 - OEIS

%I #27 Sep 08 2022 08:44:42

%S 4,121,400,841,1444,2209,3136,4225,5476,6889,8464,10201,12100,14161,

%T 16384,18769,21316,24025,26896,29929,33124,36481,40000,43681,47524,

%U 51529,55696,60025,64516,69169

%N a(n) = (9*n + 2)^2.

%H Vincenzo Librandi, <a href="/A017186/b017186.txt">Table of n, a(n) for n = 0..10000</a>

%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).

%F a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3); a(0)=4, a(1)=121, a(2)=400. - _Harvey P. Dale_, Apr 16 2013

%F G.f.: ( -4 - 109*x - 49*x^2 ) / (x-1)^3. - _R. J. Mathar_, Jul 14 2016

%p seq((9*n+2)^2,n=0..30); # _Muniru A Asiru_, Oct 20 2018

%t (9Range[0,30]+2)^2 (* or *) LinearRecurrence[{3,-3,1},{4,121,400},30] (* _Harvey P. Dale_, Apr 16 2013 *)

%o (Magma) [(9*n+2)^2: n in [0..35]]; // _Vincenzo Librandi_, Jul 23 2011

%o (PARI) a(n)=(9*n+2)^2 \\ _Charles R Greathouse IV_, Jun 17 2017

%o (GAP) List([0..30],n->(9*n+2)^2); # _Muniru A Asiru_, Oct 20 2018

%K nonn,easy

%O 0,1

%A _N. J. A. Sloane_