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A165428 a(1) = 1, a(2) = 10; thereafter a(n) = Product_{1 <= i <= n-1} a(i).

%I A165428 #16 Nov 30 2021 12:20:45
%S A165428 1,10,10,100,10000,100000000,10000000000000000,
%T A165428 100000000000000000000000000000000,
%U A165428 10000000000000000000000000000000000000000000000000000000000000000
%N A165428 a(1) = 1, a(2) = 10; thereafter a(n) = Product_{1 <= i <= n-1} a(i).
%H A165428 G. C. Greubel, <a href="/A165428/b165428.txt">Table of n, a(n) for n = 1..12</a>
%F A165428 a(n) = 10^(2^(n-3)) = A011557(2^(n-3)) = 10^A000079(n-3).
%F A165428 a(1) = 1, a(2) = 10, a(3) = 10, and for n > 3 a(n) = (a(n-1))^2.
%t A165428 a[1] = 1; a[2] = 10; a[n_] := Times @@ Array[a, n - 1]; Array[a, 9] (* _Robert G. Wilson v_, Oct 13 2009 *)
%t A165428 Join[{1,10},NestList[#^2&,10,10]] (* _Harvey P. Dale_, Nov 30 2021 *)
%o A165428 (PARI) {a(n) = if(n==1, 1, if(n==2, 10, prod(j=1,n-1, a(j))))};
%o A165428 for(n=1,10, print1(a(n), ", ")) \\ _G. C. Greubel_, Oct 19 2018
%K A165428 nonn
%O A165428 1,2
%A A165428 _Jaroslav Krizek_, Sep 17 2009
%E A165428 Name changed, formula edited by _Robert G. Wilson v_, Oct 13 2009
%E A165428 Edited by _N. J. A. Sloane_, Oct 15 2009