%I #21 Mar 06 2019 22:15:14

%S 1,10,77,554,3909,27426,192109,1345018,9415637,65910482,461375421,

%T 3229632042,22607432485,158252043778,1107764339213,7754350440026,

%U 54280453211253,379963172740914,2659742209710685

%N Expansion of 1/((1-x)(1-2x)(1-7x)).

%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (10,-23,14).

%F a(n) = (49*7^n - 24*2^n + 5)/30. - _Bruno Berselli_, Feb 09 2011

%F a(0)=1, a(n) = 7*a(n-1) + 2^(n+1) - 1. - _Vincenzo Librandi_, Feb 09 2011

%p a:=n->sum((7^(n-j+1)-2^(n-j+1))/5, j=0..n+1): seq(a(n), n=0..19); # _Zerinvary Lajos_, Jan 15 2007

%t CoefficientList[Series[1/((1-x)(1-2x)(1-7x)),{x,0,20}],x](* or *) LinearRecurrence[{10,-23,14},{1,10,77},20] (* _Harvey P. Dale_, Mar 06 2019 *)

%K nonn

%O 0,2

%A _N. J. A. Sloane_