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A027855 Antimutinous 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. 4
2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 25, 26, 27, 28, 29, 31, 32, 33, 34, 35, 37, 38, 39, 41, 42, 43, 44, 46, 47, 49, 50, 51, 52, 53, 54, 55, 57, 58, 59, 61, 62, 64, 65, 66, 67, 68, 69, 71, 73, 74, 75, 76, 77, 78, 79, 81, 82, 83, 85, 86, 87 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Ivan Neretin, Table of n, a(n) for n = 1..10000

MAPLE

A006530 := proc(n) local ifs ; if n = 1 then 1; else ifs := ifactors(n)[2] ; max(seq( op(1, k), k=ifs)) ; fi ; end: isA027855 := proc(n) local p, k, pk; if n <= 1 then false; else p := A006530(n) ; pk := p ; while n mod ( pk*p) = 0 do pk := pk*p ; od: if n< p*pk then true ; else false ; fi ; fi ; end: for n from 2 to 120 do if isA027855(n) then printf("%d, ", n) ; fi ; od: # R. J. Mathar, Dec 02 2007

MATHEMATICA

Select[Range@100, #1^(#2 + 1) & @@ FactorInteger[#][[-1]] > # &] (* Ivan Neretin, Jul 09 2015 *)

PROG

(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. A027854.

Sequence in context: A085235 A160453 A299702 * A031996 A023753 A035332

Adjacent sequences:  A027852 A027853 A027854 * A027856 A027857 A027858

KEYWORD

nonn

AUTHOR

Leroy Quet

EXTENSIONS

More terms from R. J. Mathar, Dec 02 2007

STATUS

approved

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Last modified March 25 10:16 EDT 2019. Contains 321470 sequences. (Running on oeis4.)