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 A156812 a(n) = 225*n^2 - 199*n + 44. 1

%I

%S 44,70,546,1472,2848,4674,6950,9676,12852,16478,20554,25080,30056,

%T 35482,41358,47684,54460,61686,69362,77488,86064,95090,104566,114492,

%U 124868,135694,146970,158696,170872,183498,196574,210100,224076,238502,253378

%N a(n) = 225*n^2 - 199*n + 44.

%C 900*a(n) + 1 = (450*n - 199)^2. - _Vincenzo Librandi_, Feb 08 2012

%H Vincenzo Librandi, <a href="/A156812/b156812.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 G.f.: (-44 + 62*x - 468*x^2)/(x-1)^3. - _Vincenzo Librandi_, Feb 08 2012

%F a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3). - _Vincenzo Librandi_, Feb 08 2012

%t LinearRecurrence[{3, -3, 1}, {44, 70, 546}, 40] (* _Vincenzo Librandi_, Feb 08 2012 *)

%o (PARI) a(n)=225*n^2-199*n+44 \\ _Charles R Greathouse IV_, Dec 23 2011

%o (MAGMA) I:=[44, 70, 546]; [n le 3 select I[n] else 3*Self(n-1)-3*Self(n-2)+1*Self(n-3): n in [1..40]]; // _Vincenzo Librandi_, Feb 08 2012

%K nonn,easy

%O 0,1

%A _Vincenzo Librandi_, Feb 16 2009

%E Offset corrected by _R. J. Mathar_, Aug 18 2009

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Last modified May 13 19:36 EDT 2021. Contains 343868 sequences. (Running on oeis4.)