A016181 - OEIS

%I #20 Nov 16 2020 12:49:34

%S 1,17,219,2533,27731,294117,3058819,31411733,319882131,3239174917,

%T 32674224419,328719570933,3301036996531,33107258975717,

%U 331750812830019,3322255689810133,33255789828670931,332790528800696517

%N Expansion of 1/((1-7x)(1-10x)).

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (17,-70).

%F (10^(n+1) - 7^(n+1))/3. - Lambert Klasen (lambert.klasen(AT)gmx.net), Feb 05 2005

%F a(n) = 10*a(n-1) + 7^n, a(0)=1. - _Vincenzo Librandi_, Feb 09 2011

%F a(n) = 17*a(n-1) - 70*a(n-2), a(0)=1, a(1)=17. - _Vincenzo Librandi_, Feb 09 2011

%t Join[{a=1,b=17},Table[c=17*b-70*a;a=b;b=c,{n,40}]] (* _Vladimir Joseph Stephan Orlovsky_, Feb 09 2011 *)

%t CoefficientList[Series[1/((1-7x)(1-10x)),{x,0,30}],x] (* or *) LinearRecurrence[ {17,-70},{1,17},30] (* _Harvey P. Dale_, Nov 16 2020 *)

%o (PARI) for(n=1,10,print1((10^n-7^n)/3,","))

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_