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a(n) = (10*n + 7)^2.
2

%I #20 Sep 08 2022 08:44:42

%S 49,289,729,1369,2209,3249,4489,5929,7569,9409,11449,13689,16129,

%T 18769,21609,24649,27889,31329,34969,38809,42849,47089,51529,56169,

%U 61009,66049,71289,76729,82369,88209

%N a(n) = (10*n + 7)^2.

%H Vincenzo Librandi, <a href="/A017354/b017354.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) = 40*A000566(n+1) + 9. - Ken Rosenbaum, Dec 02 2009

%F G.f.: ( -49-142*x-9*x^2 ) / (x-1)^3. - _R. J. Mathar_, Mar 21 2016

%t Table[(10n+7)^2,{n,0,24}]

%o (Magma) [(10*n+7)^2: n in [0..35]]; // _Vincenzo Librandi_, Aug 03 2011

%o (PARI) a(n)=(10*n+7)^2 \\ _Charles R Greathouse IV_, Jun 17 2017

%K nonn,easy

%O 0,1

%A _N. J. A. Sloane_