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a(n) = 1 + 17^n.
2

%I #26 Jul 22 2019 21:32:28

%S 2,18,290,4914,83522,1419858,24137570,410338674,6975757442,

%T 118587876498,2015993900450,34271896307634,582622237229762,

%U 9904578032905938,168377826559400930,2862423051509815794,48661191875666868482,827240261886336764178,14063084452067724991010

%N a(n) = 1 + 17^n.

%C Sum of n-th powers of divisors of 17.

%H Vincenzo Librandi, <a href="/A224384/b224384.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,-17).

%F a(n) = A001026(n) + 1.

%F G.f.: 1/(1-x) + 1/(1-17*x).

%F E.g.f.: exp(x) + exp(17*x).

%F a(n) = 18*a(n-1) - 17*a(n-2) with a(0) = 2, a(1) = 18.

%t 17^Range[0,20]+1 (* _Harvey P. Dale_, Jul 19 2019 *)

%Y Cf. A001026.

%Y Similar sequences: A000051, A034472, A001576, A034474, A034488, A034491, A034496, A034513, A034517, A034524, A034660, A141012, A141013, A141014, A020514, A034661, A034662, A034663, A034664, A034665, A034666, A034667, A034668, A034669, A020516, A034671, A034672, A034673, A034674, A034675.

%K nonn,easy

%O 0,1

%A _Philippe Deléham_, Apr 05 2013