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%I #10 Aug 19 2016 04:33:57
%S 1,2,3,6,15,36,94,256,729,2154,6583,20736,67156,223150,759375,2642246,
%T 9387369,34012224,125537306,471556032,1801088541,6989288907,
%U 27536796143,110075314176,446169698824,1832746290156,7625597484987,32122422687591
%N a(n) = round((n^n)^(1/3)).
%H Chai Wah Wu, <a href="/A147773/b147773.txt">Table of n, a(n) for n = 1..500</a>
%F a(n) = A105209(A000312(n)). - _Michel Marcus_, Aug 19 2016
%t lst={};Do[AppendTo[lst,Round[(n^n)^(1/3)]],{n,40}];lst
%o (Python)
%o from gmpy2 import iroot_rem
%o def A147773(n):
%o i, j = iroot_rem(n**n,3)
%o return int(i+int(8*j >= 6*i*(2*i+1)+1)) # _Chai Wah Wu_, Aug 16 2016
%Y Cf. A105209, A000312.
%K nonn
%O 1,2
%A _Vladimir Joseph Stephan Orlovsky_, Nov 12 2008