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%I #14 Mar 27 2021 19:02:28
%S 3,27,19683,7625597484987,443426488243037769948249630619149892803
%N a(n) = 3^(3^n).
%C a(n+1) = a(n) written in base 3 and read as if in base 27 (and recorded in base 10).
%C Number of distinct n-ary operators in a ternary logic. - _Ross Drewe_, Feb 13 2008
%C The next term has 116 digits. - _Harvey P. Dale_, Mar 28 2019
%F a(n) = a(n-1)^3.
%t NestList[#^3&,3,5] (* _Harvey P. Dale_, Mar 28 2019 *)
%o (Python)
%o print([3**(3**n) for n in range(5)]) # _Michael S. Branicky_, Mar 27 2021
%Y Cf. A001146, A023365.
%K nonn
%O 0,1
%A _Henry Bottomley_, Jul 12 2000
%E Next term is too big to include.