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A069900
Integer quotient of largest and smallest prime factors of n is greater than one.
7
10, 14, 20, 21, 22, 26, 28, 30, 33, 34, 38, 39, 40, 42, 44, 46, 50, 51, 52, 55, 56, 57, 58, 60, 62, 63, 65, 66, 68, 69, 70, 74, 76, 78, 80, 82, 84, 85, 86, 87, 88, 90, 92, 93, 94, 95, 98, 99, 100, 102, 104, 105, 106, 110, 111, 112, 114, 115, 116, 117, 118, 119, 120
OFFSET
1,1
COMMENTS
Also numbers having at least one prime factor greater than twice the smallest prime factor: complement of A081306; A081303(a(n)) > 0. - Reinhard Zumkeller, Mar 17 2003
LINKS
FORMULA
A069897(n) = floor(P/p) > 1, where P is the largest, p is the least prime-factor of n.
EXAMPLE
Composites with at least two and sufficiently deviating prime factors are here, like 2q, where q = prime >= 5: {10,...,254}. Numbers with such divisors like 30 are also included.
MATHEMATICA
Select[Range@ 120, #[[-1]] > 2 #[[1]] &@ FactorInteger[#][[All, 1]] &] (* Michael De Vlieger, Dec 08 2018 *)
CROSSREFS
Cf. A069897.
Sequence in context: A131693 A255532 A307516 * A073492 A073493 A162685
KEYWORD
nonn
AUTHOR
Labos Elemer, Apr 10 2002
EXTENSIONS
More terms from Reinhard Zumkeller, Mar 17 2003
STATUS
approved