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%I #24 Mar 20 2024 15:40:46
%S 2,3,6,36,1296,1679616,2821109907456,7958661109946400884391936,
%T 63340286662973277706162286946811886609896461828096
%N a(1) = 2, a(2) = 3, a(n) = 6^(2^(n-3)) for n >= 3.
%C Except for first three terms, a(n) = (a(n-1))^2.
%C Essentially the same as A165424. - _R. J. Mathar_, Feb 21 2010
%H G. C. Greubel, <a href="/A173501/b173501.txt">Table of n, a(n) for n = 1..13</a>
%F a(n) = Product_{i=1..n-1} a(i) with a(1) = 2 and a(2) = 3.
%F a(n) = 6^(2^(n-3)) = A000400(A000079(n-3)) for n>2.
%t Table[If[n<3, n+1, 6^(2^(n-3))], {n,10}] (* _G. C. Greubel_, Apr 25 2021 *)
%o (SageMath) [2,3]+[6^(2^(n-3)) for n in (3..10)] # _G. C. Greubel_, Apr 25 2021
%o (PARI) a(n) = if(n<=2, n+1, 6^(2^(n-3))) \\ _Felix Fröhlich_, Apr 25 2021
%Y Cf. A000079, A000400, A165424.
%K nonn
%O 1,1
%A _Giovanni Teofilatto_, Feb 20 2010
%E Definition corrected by _Glenn Tesler_, Aug 19 2017
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