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A027854 Mutinous numbers: n>1 such that n/p^k > p, where p is the largest prime dividing n and p^k is the highest power of p dividing n. 8
12, 24, 30, 36, 40, 45, 48, 56, 60, 63, 70, 72, 80, 84, 90, 96, 105, 108, 112, 120, 126, 132, 135, 140, 144, 150, 154, 160, 165, 168, 175, 176, 180, 182, 189, 192, 195, 198, 200, 208, 210, 216, 220, 224, 225, 231, 234, 240, 252, 260, 264, 270, 273, 275, 280 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers n > 1 such that n/A053585(n) > A006530(n). - Michael De Vlieger, Jul 13 2017

If p = A006530(a(n)) then p * a(n) is in the sequence. E.g. As 12 is in the sequence with Gpf(12) = A006530(12) = 3, 12*3^k is in the sequence for k > 0. Conjecture: if m is in the sequence then so is A003961(m). - David A. Corneth, Jul 13 2017

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..10000

EXAMPLE

From Michael De Vlieger, Jul 13 2017: (Start)

12 is a term since 12/A053585(12) = 12/3 = 4, A006530(12) = 3, and 4 > 3.

30 is a term since 30/A053585(30) = 30/5 = 6, A006530(30) = 5, and 6 > 5.

(End)

MATHEMATICA

Select[Range@ 280, Function[n, (n/Apply[Power, Last@ #]) > #[[-1, 1]] &@ FactorInteger[n]]] (* Michael De Vlieger, Jul 13 2017 *)

PROG

(PARI) isok(n) = {my(f = factor(n)); my(maxf = #f~); my(p = f[maxf, 1]); my(pk = f[maxf, 2]); (n/p^pk) > p; } \\ Michel Marcus, Jan 16 2014

(Python)

from sympy import factorint, primefactors

def a053585(n):

    if n==1: return 1

    p = primefactors(n)[-1]

    return p**factorint(n)[p]

print [n for n in xrange(2, 301) if n/a053585(n)>primefactors(n)[-1]] # Indranil Ghosh, Jul 13 2017

CROSSREFS

Cf. A006530, A027855, A053585.

Sequence in context: A182225 A074697 A289484 * A009096 A010814 A098714

Adjacent sequences:  A027851 A027852 A027853 * A027855 A027856 A027857

KEYWORD

nonn

AUTHOR

Leroy Quet.

EXTENSIONS

Extended by Ray Chandler, Nov 17 2008

Offset changed to 1 by Michel Marcus, Jan 16 2014

STATUS

approved

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Last modified March 23 14:17 EDT 2019. Contains 321431 sequences. (Running on oeis4.)