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A085232 In canonical prime factorization: power of smallest prime factor is less than power of greatest prime factor. 3
6, 10, 14, 15, 18, 20, 21, 22, 26, 28, 30, 33, 34, 35, 36, 38, 39, 42, 44, 46, 50, 51, 52, 54, 55, 57, 58, 60, 62, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 82, 84, 85, 86, 87, 88, 90, 91, 92, 93, 94, 95, 98, 99, 100, 102, 104, 105, 106, 108, 110, 111, 114, 115 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A028233(a(n)) < A053585(a(n));

p*a(n) is a term for all primes p with A020639(a(n))<p < A006530(a(n));

a(n)=A057714(n-1) for n<28: a(28)=60, A057714(28-1)=62.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..2500

EXAMPLE

60 = 2^2 * 3 * 5 with 2^2=4 < 5, therefore 60 is a term.

MATHEMATICA

spfQ[n_]:=Module[{fi=FactorInteger[n]}, Length[fi]>1&&fi[[1, 1]]^fi[[1, 2]] < fi[[-1, 1]]^fi[[-1, 2]]]; Select[Range[120], spfQ] (* Harvey P. Dale, Jul 30 2018 *)

CROSSREFS

Cf. A085231.

Sequence in context: A063774 A068993 A138592 * A085234 A057714 A143907

Adjacent sequences:  A085229 A085230 A085231 * A085233 A085234 A085235

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jun 22 2003

STATUS

approved

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Last modified October 23 22:10 EDT 2019. Contains 328373 sequences. (Running on oeis4.)