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 A175760 Numbers n such that d(n + d(n)) = d(n), where d(n) is the sum of the distinct primes dividing n. 3
 1, 2, 39, 95, 119, 182, 2130, 2183, 2356, 2623, 3059, 3431, 3825, 6680, 9588, 10170, 10679, 11790, 14039, 14111, 15030, 16199, 16762, 16799, 17766, 19669, 22218, 24505, 26352, 26353, 34443, 34765, 34875, 36594, 37843, 39121, 39479, 39697, 42210, 44051, 45346 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The sum of the distinct primes dividing n (A008472) sometimes called sopf(n). 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 LINKS T. D. Noe, Table of n, a(n) for n = 1..1000 EXAMPLE 39 is in the sequence because sopf(39) = 16 and sopf(39 + sopf(39)) = sopf(55 ) = 16. MATHEMATICA d[n_] := Plus @@ Transpose[FactorInteger[n]][[1]]; Join[{1}, Select[Range[2, 50000], d[# + d[#]] == d[#] &]] CROSSREFS Sequence in context: A078733 A201360 A227904 * A080920 A086338 A329552 Adjacent sequences:  A175757 A175758 A175759 * A175761 A175762 A175763 KEYWORD nonn AUTHOR Michel Lagneau, Aug 28 2010 STATUS approved

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Last modified December 14 03:31 EST 2019. Contains 329978 sequences. (Running on oeis4.)