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A333961 Numbers k with property that k is the least logarithmically smooth numbers (meaning largest prime factor of k is less than log(k)) having squarefree kernel equal to squarefree kernel of k. 0
8, 24, 27, 150, 160, 225, 625, 1120, 1134, 1225, 1260, 1323, 1372, 1575, 2401, 59895, 60368, 60500, 60984, 61600, 61952, 62370, 63360, 63525, 63888, 65219, 67375, 68607, 72171, 73205, 161051, 443625, 445900, 446160, 446875, 447174, 448448, 449280, 449878, 450450 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primitive sequence underlying A137845. If k is in this sequence then any number larger than k having the same squarefree kernel is in the sequence.

LINKS

Table of n, a(n) for n=1..40.

EXAMPLE

8 is in the sequence as the largest prime factor of 8 is 2 and log(8) > 2 and 8 is the least positive integer with this property and squarefree kernel 2.

MATHEMATICA

rads = seq = {}; Do[rad = Times @@ (p = First /@ FactorInteger[n]); pmax = Max[p]; If[pmax < Log[n] && ! MemberQ[rads, rad], AppendTo[rads, rad]; AppendTo[seq, n]], {n, 1, 5*10^5}]; seq (* Amiram Eldar, Apr 12 2020 *)

CROSSREFS

Cf. A007947, A137845.

Sequence in context: A048109 A068781 A212861 * A038524 A261394 A162829

Adjacent sequences:  A333958 A333959 A333960 * A333962 A333963 A333964

KEYWORD

nonn

AUTHOR

David A. Corneth, Apr 12 2020

STATUS

approved

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Last modified June 23 21:56 EDT 2021. Contains 345402 sequences. (Running on oeis4.)