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%I #30 Aug 23 2020 02:09:41
%S 88,169,286,484,598,682,808,844,897,961,1339,1573,1599,1878,1986,2266,
%T 2488,2626,2662,2743,2938,3193,3289,3751,3887,4084,4444,4642,4738,
%U 4804,4972,4976,4983,5566,5665,5764,5797,5863
%N 1/2-Smith numbers.
%H Amiram Eldar, <a href="/A050224/b050224.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1000 from Harvey P. Dale)
%H Shyam Sunder Gupta, <a href="http://www.shyamsundergupta.com/smith.htm">Smith Numbers</a>.
%H Wayne 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, Vol. 25, No. 1 (1987), pp. 76-80.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SmithNumber.html">Smith Numbers</a>
%e 88 is a 2^(-1) Smith number because the digit sum of 88, i.e., S(88) = 8 + 8 = 16, which is equal to twice the sum of the digits of its prime factors, i.e., 2 * Sp (88) = 2 * Sp (11 * 2 * 2 * 2) = 2 * (1 + 1 + 2 + 2 + 2) = 16.
%t snoQ[n_]:=Total[IntegerDigits[n]]==2Total[Flatten[IntegerDigits/@ Flatten[ Table[First[#],{Last[#]}]&/@FactorInteger[n]]]]; Select[Range[ 6000], snoQ] (* _Harvey P. Dale_, Oct 15 2011 *)
%Y Cf. A006753, A050225.
%K nonn,base
%O 1,1
%A _Eric W. Weisstein_
%E More terms from _Shyam Sunder Gupta_, Mar 11 2005
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