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7^n - 3^n + 1.
8

%I #13 Oct 07 2015 11:15:01

%S 1,5,41,317,2321,16565,116921,821357,5758241,40333925,282416201,

%T 1977149597,13840755761,96887416085,678218289881,4747547161037,

%U 33232887522881,232630384847045,1628413210489961,11398894023111677

%N 7^n - 3^n + 1.

%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (11,-31,21).

%F G.f.: 1/(1-7*x)-1/(1-3*x)+1/(1-x).

%F E.g.f.: e^(7*x)-e^(3*x)+e^x.

%F a(n) = 10*a(n-1)-21*a(n-2)+12 with a(0)=1, a(1)=5. - _Vincenzo Librandi_, Jul 21 2010

%o (PARI) a(n)=7^n-3^n+1 \\ _Charles R Greathouse IV_, Oct 07 2015

%Y Cf. A155596, A155597, A155598, A155599, A155600, A155601, A155602, A155603, A155604, A155605, A155606, A155607, A155608, A155609, A155610, A155611.

%K nonn,easy

%O 0,2

%A _Mohammad K. Azarian_, Jan 26 2009