%I #12 Apr 16 2020 01:23:22
%S 1,1,30,93,1,19,80,4,30,80,1,30,93,4,10,80,24,30,80,28,30,93,8,30,80,
%T 28,19,93,8,30,93,4,30,80,8,30,93,8,10,93,1,10,80,8,10,93,28,30,80,28,
%U 19,80,28,30,93,8,30,93,8,30,80,24,19,93,28,30,80,4,30,80,4,30
%N Periods of sum of 9th powers of digits iterated until the sequence becomes periodic.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Digitaddition.html">Digitaddition</a>
%K nonn,base
%O 0,3
%A _Eric W. Weisstein_
%E Missing a(0)=1 inserted by _Sean A. Irvine_, Apr 15 2020