A188526 - OEIS

%I #31 Jun 30 2023 16:53:37

%S 28,245,2191,19691,177163,1594355,14348971,129140291,1162261723,

%T 10460353715,94143179851,847288611491,7625597489083,68630377373075,

%U 617673396300331,5559060566588291,50031545099065243,450283905891128435,4052555153019238411

%N a(n) = 3^(2*n + 3) + 2^n.

%C All terms are multiples of 7: A082784(a(n)) = 1, A188527(n) = a(n)/7.

%D Kees Doets and Jan van Eijck, The Haskell Road to Logic, Maths and Programming, The King's College Publications, London 2006. Cf. exercise 7.9, p 239.

%H Vincenzo Librandi, <a href="/A188526/b188526.txt">Table of n, a(n) for n = 0..500</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (11, -18).

%F a(n) = A013708(n+1) + A000079(n).

%F G.f.: 7*(4-9*x)/((1-2*x)*(1-9*x)). - _Bruno Berselli_, Jul 17 2011

%t Table[3^(2n+3)+2^n,{n,0,20}]  (* _Harvey P. Dale_, Apr 09 2011 *)

%o (Magma) [3^(2*n + 3) + 2^n: n in [0..20]]; // _Vincenzo Librandi_, Jul 17 2011

%Y Cf. A000079, A013708, A082784, A188527.

%K nonn,easy

%O 0,1

%A _Reinhard Zumkeller_, Apr 03 2011