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A050780
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(n + sopf_n = m) and (m - sopf_m = n). Sequence gives values of n.
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2
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39, 60, 70, 95, 119, 240, 2079, 2130, 2183, 3000, 3125, 3431, 4250, 6293, 6468, 9310, 10164, 10241, 10679, 13433, 14039, 14111, 15561, 16199, 16799, 23552, 24601, 27004, 28116, 28560, 31416, 32883, 42112, 44268, 52193, 52969, 53754, 59072
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,1
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COMMENTS
| sopf_n = sum of the prime factors of n (with multiplicity).
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EXAMPLE
| E.g. 39 + (3+13) = 55 - (5+11) = 39.
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MATHEMATICA
| sopf[n_] := Total[Apply[Times, FactorInteger[n], {1}]]; ok[n_] := n + sopf[n] - sopf[n + sopf[n]] == n; Select[Range[59200], ok] (* From Jean-François Alcover, Apr 18 2011 *)
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CROSSREFS
| Cf. A050781, A050703-A050710.
Sequence in context: A156333 A116281 A168530 * A039353 A043176 A043956
Adjacent sequences: A050777 A050778 A050779 * A050781 A050782 A050783
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KEYWORD
| nonn,nice
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AUTHOR
| Patrick De Geest (pdg(AT)worldofnumbers.com), Sep 15 1999.
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