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A069900 Integer quotient of largest and smallest prime factors of n is greater than one. 5
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 (list; graph; refs; listen; history; text; internal format)
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

Michael De Vlieger, Table of n, a(n) for n = 1..10000

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

Adjacent sequences:  A069897 A069898 A069899 * A069901 A069902 A069903

KEYWORD

nonn

AUTHOR

Labos Elemer, Apr 10 2002

EXTENSIONS

More terms from Reinhard Zumkeller, Mar 17 2003

STATUS

approved

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Last modified April 4 19:22 EDT 2020. Contains 333229 sequences. (Running on oeis4.)