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%I #10 Jul 07 2012 23:47:53
%S 1,2,39,95,119,182,2130,2183,2356,2623,3059,3431,3825,6680,9588,10170,
%T 10679,11790,14039,14111,15030,16199,16762,16799,17766,19669,22218,
%U 24505,26352,26353,34443,34765,34875,36594,37843,39121,39479,39697,42210,44051,45346
%N Numbers n such that d(n + d(n)) = d(n), where d(n) is the sum of the distinct primes dividing n.
%C The sum of the distinct primes dividing n (A008472) sometimes called sopf(n).
%C d(1) = 0 because 1 has no prime divisors. So 1 is in this sequence because d(1+0) = d(1). - _T. D. Noe_, Jul 06 2012
%H T. D. Noe, <a href="/A175760/b175760.txt">Table of n, a(n) for n = 1..1000</a>
%e 39 is in the sequence because sopf(39) = 16 and sopf(39 + sopf(39)) = sopf(55 ) = 16.
%t d[n_] := Plus @@ Transpose[FactorInteger[n]][[1]]; Join[{1}, Select[Range[2,50000], d[# + d[#]] == d[#] &]]
%K nonn
%O 1,2
%A _Michel Lagneau_, Aug 28 2010
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