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%I #21 Sep 08 2022 08:45:55
%S 1,-7,-23,-47,-79,-119,-167,-223,-287,-359,-439,-527,-623,-727,-839,
%T -959,-1087,-1223,-1367,-1519,-1679,-1847,-2023,-2207,-2399,-2599,
%U -2807,-3023,-3247,-3479,-3719,-3967,-4223,-4487,-4759,-5039,-5327,-5623
%N a(n)=1-4*n-4*n^2.
%C Hankel transform of A184881.
%H Vincenzo Librandi, <a href="/A184882/b184882.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F G.f.: (1-10*x+x^2)/(1-x)^3.
%F a(n)=+3*a(n-1)-3*a(n-2)+1*a(n-3) for n>=3.
%F a(0)=1, a(n)=a(n-1)-8*n. - _Vincenzo Librandi_, Jan 25 2011
%t Table[1-4n-4n^2,{n,0,50}] (* or *) LinearRecurrence[{3,-3,1},{1,-7,-23},50] (* _Harvey P. Dale_, Feb 21 2014 *)
%o (Magma) [1-4*n-4*n^2: n in [0..60]]; // _Vincenzo Librandi_, Feb 23 2014
%o (PARI) a(n)=1-4*n-4*n^2 \\ _Charles R Greathouse IV_, Jun 17 2017
%K sign,easy
%O 0,2
%A _Paul Barry_, Jan 24 2011