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%I #15 Jan 22 2019 02:52:14
%S 399996663,666609999,669969663,690696969,699966663,2789929969,
%T 3066999963,3366339999,3366999933,3399696663,3399996633,3666699663,
%U 3669933993,3933969693,6066690999,6069996663,6099996633,6393996933,6399636963,6666009999,6669669633,6966939633
%N 1/5-Smith numbers.
%H S. S. Gupta, <a href="http://www.shyamsundergupta.com/smith.htm">Smith Numbers</a>.
%H W. L. McDaniel, <a href="http://www.fq.math.ca/Scanned/25-1/mcdaniel.pdf">The Existence of infinitely Many k-Smith numbers</a>, Fibonacci Quarterly, 25(1987), pp. 76-80.
%e 399996663 is a 5^(-1) Smith number because the digit sum of 399996663, i.e., S(399996663) = 3 + 9 + 9 + 9 + 9 + 6 + 6 + 6 + 3 = 60, which is equal to 5 times the sum of the digits of its prime factors, i.e., 5*Sp(399996663) = 5*Sp(3*11*101*120011) = 5*(3 + 1 + 1 + 1 + 0 + 1 + 1 + 2 + 0 + 0 + 1 + 1) = 60.
%Y Cf. A006753.
%K base,nonn
%O 1,1
%A _Shyam Sunder Gupta_, Mar 16 2005
%E a(6)-a(22) from _Donovan Johnson_, Sep 20 2011
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