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A126855 Numbers n such that, if n = product{p|n} p^c(n,p), each c(n,p) is a positive integer and each p is a distinct prime, then the smallest prime-power p^c(n, p) is not a power of the smallest prime dividing n. 2
12, 24, 40, 45, 48, 56, 60, 63, 80, 84, 96, 112, 120, 132, 135, 144, 156, 160, 168, 175, 176, 189, 192, 204, 208, 224, 228, 240, 264, 275, 276, 280, 288, 297, 300, 312, 315, 320, 325, 336, 348, 351, 352, 360, 372, 384, 405, 408, 416, 420, 425, 440, 444, 448 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..54.

EXAMPLE

3600 is included because 3600 = 2^4 * 3^2 * 5^2 and the smallest prime-power (which is largest prime-power of its prime to divide 3600), 3^2 = 9, is not a power of the smallest prime to divide 3600, which is 2.

MATHEMATICA

fQ[n_] := Block[{p = Power @@@ FactorInteger[n]}, First[p] != Min[p]]; Select[Range[460], fQ] (* Ray Chandler, Mar 25 2007 *)

CROSSREFS

Cf. A020639, A034684, A102749.

Sequence in context: A098242 A139406 A140831 * A102749 A085231 A057715

Adjacent sequences:  A126852 A126853 A126854 * A126856 A126857 A126858

KEYWORD

nonn

AUTHOR

Leroy Quet, Mar 23 2007

EXTENSIONS

Extended by Ray Chandler, Mar 25 2007

STATUS

approved

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Last modified September 29 11:06 EDT 2020. Contains 337428 sequences. (Running on oeis4.)