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%I #7 Feb 08 2013 18:00:15
%S 3,5,15,225,50625,2562890625,6568408355712890625,
%T 43143988327398919500410556793212890625,
%U 1861403728794734215467410604755702820123364205073812627233564853668212890625
%N a(n) = product_{i=1..n-1} a(i), with a(1) = 3 and a(2) = 5.
%C Except for first three terms, a(n) = (a(n-1))^2 .
%F a(n) = 15^(2^(n-3)), n > 2.
%t Join[{3,5},NestList[#^2&,15,7]] (* _Harvey P. Dale_, Feb 08 2013 *)
%K nonn
%O 1,1
%A _Giovanni Teofilatto_, Feb 23 2010
%E Edited by Jaroslav Krizek and R. J. Mathar, Mar 04 2010