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a(n) = 7^n + 6.
2

%I #10 Sep 08 2022 08:46:10

%S 7,13,55,349,2407,16813,117655,823549,5764807,40353613,282475255,

%T 1977326749,13841287207,96889010413,678223072855,4747561509949,

%U 33232930569607,232630513987213,1628413597910455,11398895185373149,79792266297612007,558545864083284013

%N a(n) = 7^n + 6.

%C Subsequence of A226819.

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (8,-7).

%F G.f.: (7 - 43*x) / ((1 - x)*(1 - 7*x)).

%F a(n) = 8*a(n-1) - 7*a(n-2) for n>1.

%t Table[7^n + 6, {n, 0, 30}]

%o (Magma) [7^n+6: n in [0..30]];

%Y Cf. similar sequences listed in A253208.

%Y Cf. A164783, A226819.

%K nonn,easy

%O 0,1

%A _Vincenzo Librandi_, Dec 29 2014