%I A031350
%S A031350 0,4,3,3,3,3,2,2,3,1,1,4,3,3,3,3,2,2,3,1,4,3,3,2,2,2,3,3,2,1,3,3,3,
%T A031350 2,2,2,3,3,3,1,3,2,2,3,2,3,3,2,3,1,3,2,2,2,2,2,2,2,2,1,3,2,2,3,2,3,
%U A031350 3,2,2,1,2,3,3,3,2,3,2,3,3,1,2,3,3,2,2,2,3,3,3,1,3,2,3,3,2,2,3,3,2
%N A031350 4-multiplicative persistence: number of iterations of "multiply 4th powers 
               of digits" needed to reach 0 or 1.
%H A031350 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               MultiplicativePersistence.html">Link to a section of The World of 
               Mathematics.</a>
%Y A031350 Sequence in context: A016502 A117691 A143487 this_sequence A031353 A085415 
               A059124
%Y A031350 Adjacent sequences: A031347 A031348 A031349 this_sequence A031351 A031352 
               A031353
%K A031350 nonn
%O A031350 0,2
%A A031350 Eric Weisstein (eric(AT)weisstein.com)