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Expansion of 1/((1-7x)(1-12x)).
1

%I #18 Jul 15 2018 22:04:00

%S 1,19,277,3667,46405,573667,7001653,84843379,1023885349,12326977795,

%T 148206208789,1780451832211,21379263273733,256648048295203,

%U 3080454802615285,36970205192893363,443675695245289957

%N Expansion of 1/((1-7x)(1-12x)).

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (19,-84).

%F a(n) = (12^(n+1) - 7^(n+1))/5. - Lambert Klasen (lambert.klasen(AT)gmx.net), Feb 06 2005

%F a(n) = 12*a(n-1) + 7^n, a(0)=1. - _Vincenzo Librandi_, Feb 09 2011

%F a(n) = 19*a(n-1) - 84*a(n-2), a(0)=1, a(1)=19. - _Vincenzo Librandi_, Feb 09 2011

%t Join[{a=1,b=19},Table[c=19*b-84*a;a=b;b=c,{n,40}]] (* _Vladimir Joseph Stephan Orlovsky_, Feb 14 2011 *)

%t CoefficientList[Series[1/((1-7x)(1-12x)),{x,0,20}],x] (* or *) LinearRecurrence[ {19,-84},{1,19},20] (* _Harvey P. Dale_, Jul 09 2018 *)

%o (PARI) Vec(1/((1-7*x)*(1-12*x))+O(x^99)) \\ _Charles R Greathouse IV_, Sep 26 2012

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_