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a(n) = 81*n - 22.
2

%I #26 Sep 08 2022 08:45:41

%S 59,140,221,302,383,464,545,626,707,788,869,950,1031,1112,1193,1274,

%T 1355,1436,1517,1598,1679,1760,1841,1922,2003,2084,2165,2246,2327,

%U 2408,2489,2570,2651,2732,2813,2894,2975,3056,3137,3218,3299,3380,3461,3542

%N a(n) = 81*n - 22.

%H Vincenzo Librandi, <a href="/A156796/b156796.txt">Table of n, a(n) for n = 1..1000</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1).

%F From _Vincenzo Librandi_, Mar 01 2012: (Start)

%F G.f.: x*(59 + 22*x)/(1-x)^2.

%F a(n) = 2*a(n-1) - a(n-2). (End)

%F E.g.f.: 22 - (22 - 81*x)*exp(x). - _G. C. Greubel_, Jun 26 2021

%t LinearRecurrence[{2, -1}, {59, 140}, 50] (* _Vincenzo Librandi_, Mar 01 2012 *)

%o (PARI) a(n)=81*n-22 \\ _Charles R Greathouse IV_, Dec 23 2011

%o (Magma) I:=[59, 140]; [n le 2 select I[n] else 2*Self(n-1)-Self(n-2): n in [1..50]]; // _Vincenzo Librandi_, Mar 01 2012

%o (Sage) [81*n - 22 for n in (1..50)] # _G. C. Greubel_, Jun 26 2021

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Feb 16 2009