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%I #13 Jun 10 2018 12:54:34
%S 0,0,2,2,2,2,2,2,2,3,0,4,3,2,2,3,3,2,4,3,14,4,5,4,4,5,4,5,6,6,14,5,6,
%T 5,6,6,6,5,5,6,14,7,6,8,6,7,6,8,7,7,16,6,6,8,7,8,7,7,9,7,15,8,8,7,8,8,
%U 9,8,8,8,18,12,9,9,8,9,9,9,9,9,18,10,11,11,10,11,11,10,9,10,17,11,11,10,11,10,12,12,10,11,0
%N a(n) = smallest m such that the sum of digits of n^m is greater than n, or 0 if no such m exists.
%C a(n) = smallest m such that A007953(n^m) > n, or 0 if no such m exists.
%C If n is a term of A178501, then a(n) = 0. - _Felix Fröhlich_, Jun 10 2018
%o (PARI) a(n) = if(sumdigits(n) < 2, return(0), my(m=2); while(1, if(sumdigits(n^m) > n, return(m)); m++)) \\ _Felix Fröhlich_, Jun 10 2018
%Y Cf. A007953, A038206, A178501, A305707.
%K base,nonn
%O 0,3
%A _Max Alekseyev_, Jun 08 2018
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