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a(n) = (3*11^n - 7^n)/2.
3

%I #15 Mar 21 2023 18:34:58

%S 1,13,157,1825,20761,233173,2598517,28818985,318655921,3516744733,

%T 38764899277,426978842545,4700721921481,51735623710693,

%U 569285638838437,6263498473368505,68907978330073441,758054227491947053,8339061763439391997,91732936225029132865,1009085096265691207801

%N a(n) = (3*11^n - 7^n)/2.

%C Binomial transform of A165150. Inverse binomial transform of A165152.

%H Vincenzo Librandi, <a href="/A165151/b165151.txt">Table of n, a(n) for n = 0..200</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (18,-77).

%F a(n) = 18*a(n-1) - 77*a(n-2) for n > 1; a(0) = 1, a(1) = 13.

%F G.f.: (1 - 5*x)/((1 - 7*x)*(1 - 11*x)).

%F E.g.f.: exp(7*x)*(3*exp(4*x) - 1)/2. - _Stefano Spezia_, Mar 21 2023

%t Table[(3 11^n-7^n)/2,{n,0,20}] (* or *) LinearRecurrence[{18,-77},{1,13},20] (* _Harvey P. Dale_, Jan 28 2012 *)

%o (Magma) [ (3*11^n-7^n)/2: n in [0..17] ];

%Y Cf. A165150, A165152.

%K nonn,easy

%O 0,2

%A _Klaus Brockhaus_, Sep 15 2009