%I

%S 2,4,7,20,57,149,523,1835,6810,26222,106670,444085

%N Number of Ruth-Aaron numbers (with multiplicity) less than 10^n.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Ruth-AaronPair.html">Ruth-Aaron Pair</a>

%Y Cf. A039752.

%K nonn,more

%O 1,1

%A _Eric W. Weisstein_, Dec 16 2004

%E Offset corrected and a(9)-a(12) from _Donovan Johnson_, Dec 14 2010