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A141495 a(n) = 3*a(n-1) for n>2; a(0)=1, a(1)=3, a(2)=7.

%I A141495 #20 Jan 28 2025 07:56:25
%S A141495 1,3,7,21,63,189,567,1701,5103,15309,45927,137781,413343,1240029,
%T A141495 3720087,11160261,33480783,100442349,301327047,903981141,2711943423,
%U A141495 8135830269,24407490807,73222472421,219667417263,659002251789
%N A141495 a(n) = 3*a(n-1) for n>2; a(0)=1, a(1)=3, a(2)=7.
%C A141495 A sequence of the form: a(0)=1, a(1)=prime(m), a(2)=prime(m+2), a(n)=a(1)*a(n-1).
%C A141495 a(n) is divisible by 7 for n>1. - _Colin Barker_, Jan 09 2014
%H A141495 Vincenzo Librandi, <a href="/A141495/b141495.txt">Table of n, a(n) for n = 0..1000</a>
%H A141495 <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (3).
%F A141495 a(n) = A082541(n-1), n>1. - _R. J. Mathar_, Aug 27 2008
%F A141495 a(n) = 7*3^(n-2) for n>1. a(n)=3*a(n-1) for n>2. G.f.: (2*x^2-1) / (3*x-1). - _Colin Barker_, Jan 09 2014
%t A141495 a[0] = 1; a[1] = 3; a[2] = 7; a[n_] := a[n] = a[1]*a[n - 1]; Table[a[n], {n, 0, 30}]
%t A141495 Join[{1,3},NestList[3#&,7,30]] (* _Harvey P. Dale_, Aug 05 2024 *)
%Y A141495 Essentially the same as A005032 and A084215. For other examples see A141496, etc.
%K A141495 nonn,easy
%O A141495 0,2
%A A141495 _Roger L. Bagula_, Aug 10 2008
%E A141495 Edited by _N. J. A. Sloane_, Aug 16 2008