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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
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
Sequence in context: A144551 A174457 A353011 * A262983 A356078 A324508
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.)