%I #27 Sep 08 2022 08:45:54
%S 0,30,210,1290,7770,46650,279930,1679610,10077690,60466170,362797050,
%T 2176782330,13060694010,78364164090,470184984570,2821109907450,
%U 16926659444730,101559956668410,609359740010490,3656158440062970,21936950640377850,131621703842267130
%N a(n) = 6^n - 6.
%H Vincenzo Librandi, <a href="/A178672/b178672.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 (7,-6).
%F a(n) = 6*a(n-1) + 30, n>1.
%F From _R. J. Mathar_, Jan 05 2011: (Start)
%F a(n) = 30*A003464(n-1).
%F G.f.: 30*x^2 / ( (1-6*x)*(1-x) ). (End)
%F a(n) = 7*a(n-1) - 6*a(n-2). - _Vincenzo Librandi_, Jan 25 2013
%F E.g.f.: exp(6*x) - 6*exp(x) + 5. - _G. C. Greubel_, Jan 27 2019
%t 6^Range[30]- 6 (* _Vincenzo Librandi_, Jan 25 2013 *)
%t LinearRecurrence[{7,-6},{0,30},30] (* _Harvey P. Dale_, Jul 25 2020 *)
%o (Magma) [6^n-6: n in [1..30]]
%o (PARI) vector(30, n, 6^n-6) \\ _G. C. Greubel_, Jan 27 2019
%o (Sage) [6^n-6 for n in (1..30)] # _G. C. Greubel_, Jan 27 2019
%o (GAP) List([1..30], n -> 6^n-6); # _G. C. Greubel_, Jan 27 2019
%Y Cf. A003464.
%K nonn,easy
%O 1,2
%A _Vincenzo Librandi_, Dec 25 2010