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 A110821 SuperRefactorable numbers: m=A005179(n) such that k=m/n is an integer. 5
 1, 2, 12, 24, 36, 60, 180, 240, 360, 720, 1260, 1680, 3600, 5040, 6720, 10080, 15120, 20160, 25200, 32400, 55440, 60480, 100800, 110880, 181440, 221760, 226800, 277200, 665280, 720720, 810000, 907200, 1108800, 1441440, 1587600, 1995840, 2494800, 2882880, 3548160, 3603600 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Refactorable numbers, A033950, such that m=A073904(n)=A005179(n). LINKS David A. Corneth, Table of n, a(n) for n = 1..10000 EXAMPLE k = m/n = 1, 1, 2, 3, 4, 5, 10, 12, 15, 24, 35, 42, ... is an integer. For instance: 60/12=5, 180/18=10, 240/20=12, 360/24=15. MATHEMATICA t = Table[0, {2^10}]; Do[ d = DivisorSigma[0, n]; If[ d < 2^10 && t[[d]] == 0, t[[d]] = n], {n, 2882880}]; Rest[ Union[ t[[ Select[ Range[2^10], IntegerQ[ t[[ # ]]/# ] &]] ]]] (* Robert G. Wilson v, Sep 21 2005 *) CROSSREFS Cf. A033950, A005179, A007416 and A073904. Sequence in context: A144551 A174457 A353011 * A262983 A356078 A324508 Adjacent sequences: A110818 A110819 A110820 * A110822 A110823 A110824 KEYWORD nonn AUTHOR Thomas Ordowski, Sep 16 2005 EXTENSIONS More terms from Robert G. Wilson v, Sep 21 2005 Data corrected by David A. Corneth, Dec 11 2021 STATUS approved

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Last modified June 25 12:23 EDT 2024. Contains 373701 sequences. (Running on oeis4.)