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%I #24 Feb 24 2023 16:29:02
%S 4,4,9,13,13,13,4,13,4,13,13,13,13,13,18,13,13,15,13,15,13,13,13,13,
%T 18,21,15,13,15,15,18,15,15,18,15,13,17,18,15,22,15,15,15,22,13,15,13,
%U 22,22,15,4,13,13,13,13,15,17,18,13,15,15,13,13,22,17,18,21,22,13,15
%N Sums of digits of Smith numbers A006753.
%H Reinhard Zumkeller, <a href="/A050218/b050218.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SmithNumber.html">Smith Number</a>.
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Smith_number">Smith number</a>.
%F a(n) = A007953(A006753(n)).
%t d[n_]:=IntegerDigits[n]; tr[n_]:=Transpose[FactorInteger[n]]; t={}; Do[If[!PrimeQ[n]&&(x=Total[d[n]])==Total[d@tr[n][[1]]*tr[n][[2]],2],AppendTo[t,x]],{n,4,1850}]; t (* _Jayanta Basu_, Jun 04 2013 *)
%Y Cf. A006753, A050219, A050220.
%Y Cf. A202388, A050223.
%K nonn,base,less
%O 1,1
%A _Eric W. Weisstein_
%E Offset corrected by _Reinhard Zumkeller_, Dec 19 2011
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