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A164682 a(n) = 2*a(n-2) for n > 2; a(1) = 5, a(2) = 8.

%I A164682 #10 Jun 30 2023 01:07:55
%S A164682 5,8,10,16,20,32,40,64,80,128,160,256,320,512,640,1024,1280,2048,2560,
%T A164682 4096,5120,8192,10240,16384,20480,32768,40960,65536,81920,131072,
%U A164682 163840,262144,327680,524288,655360,1048576,1310720,2097152,2621440,4194304
%N A164682 a(n) = 2*a(n-2) for n > 2; a(1) = 5, a(2) = 8.
%C A164682 Interleaving of A020714 and A000079 without initial terms 1, 2, 4.
%C A164682 First differences are in A162255.
%C A164682 Binomial transform is A135532 without initial terms -1, 3. Fourth binomial transform is A164537.
%H A164682 Vincenzo Librandi, <a href="/A164682/b164682.txt">Table of n, a(n) for n = 1..1000</a>
%H A164682 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (0, 2).
%F A164682 a(n) = (9-(-1)^n)*2^(1/4*(2*n-5+(-1)^n)).
%F A164682 G.f.: x*(5+8*x)/(1-2*x^2).
%t A164682 LinearRecurrence[{0,2},{5,8},60] (* _Harvey P. Dale_, Jul 20 2022 *)
%o A164682 (Magma) [ n le 2 select 2+3*n else 2*Self(n-2): n in [1..40] ];
%Y A164682 Equals A094958 (numbers of the form 2^n or 5*2^n) without initial terms 1, 2, 4.
%Y A164682 Cf. A020714 (5*2^n), A000079 (powers of 2), A162255, A135532, A164537.
%K A164682 nonn,easy
%O A164682 1,1
%A A164682 _Klaus Brockhaus_, Aug 21 2009