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 A330412 Integers m such that sigma(m) + sigma(8*m) = 18*m. 2
 34, 568, 147328, 603971584, 9663643648, 39582416502784, 696341272098017608537735168, 765635325572111542783369494684623699968, 3615610599582728119969414707766982030374842621310535527825408, 3791242500068058721125048996612134914443116117566314438843154038784 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This is the case h = 8 of the h-perfect numbers as defined in the Harborth link. LINKS Heiko Harborth, On h-perfect numbers, Annales Mathematicae et Informaticae, 41 (2013) pp. 57-62. FORMULA a(n) = 2^A002236(n) * A050524(n). EXAMPLE 34 is a term since sigma(34) + sigma(8*34) = 612, that is 18*34. PROG (PARI) isok(m) = sigma(m) + sigma(8*m) == 18*m; CROSSREFS Cf. A000203, A000396, A002236, A050524, A136539, A281993, A330413. Sequence in context: A232320 A133720 A010950 * A089938 A126924 A035712 Adjacent sequences:  A330409 A330410 A330411 * A330413 A330414 A330415 KEYWORD nonn AUTHOR Jinyuan Wang, Feb 12 2020 STATUS approved

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Last modified January 24 19:03 EST 2022. Contains 350565 sequences. (Running on oeis4.)