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 A165442 Start with m, repeatedly find sum of prime factors until we reach a fixed point, then compute sum of numbers in trajectory except for m and the fixed point. If the resulting sum equals m, adjoin m to the sequence. 0
 20, 38, 74 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS No further terms below 10^13. Note that if the sum of the prime factors of a composite number equals itself, then it can only be 4. LINKS EXAMPLE Take 20 as example, the sum of its prime factors is 9, then we move on until we get a prime, 9=3x3, 3+3=6, and 6=2x3, 2+3=5, add all the results in the process, 9+6+5=20. 20=9+6+5, 38=21+10+7, 74=39+16+8+6+5. CROSSREFS Cf. A001414, A029908. Sequence in context: A259734 A294736 A217427 * A242532 A132606 A054288 Adjacent sequences:  A165439 A165440 A165441 * A165443 A165444 A165445 KEYWORD nonn,more,bref AUTHOR K. T. Lee (7x3(AT)21cn.com), Sep 19 2009 EXTENSIONS Edited by N. J. A. Sloane, Sep 20 2009 STATUS approved

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Last modified February 27 15:16 EST 2020. Contains 332307 sequences. (Running on oeis4.)