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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 Table of n, a(n) for n=1..3. 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: A294736 A217427 A345339 * 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 September 26 07:43 EDT 2023. Contains 365654 sequences. (Running on oeis4.)