OFFSET
1,1
COMMENTS
Complement of the union of {1} and A002035. [Correction, Nov 15 2012]
A162645 is a subsequence and this sequence is a subsequence of A162643. - Reinhard Zumkeller, Jul 08 2009
The asymptotic density of this sequence is 1 - A065463 = 0.2955577990... - Amiram Eldar, Jul 21 2020
A number k is a term iff its core (A007913) properly divides its kernel (A007947), that is iff A336643(k) > 1. - David James Sycamore, Sep 18 2023
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
MATHEMATICA
Select[Range[210], MemberQ[EvenQ[Transpose[FactorInteger[#]][[2]]], True] &] (* Harvey P. Dale, Apr 03 2012 *)
PROG
(Haskell)
a072587 n = a072587_list !! (n-1)
a072587_list = tail $ filter (any even . a124010_row) [1..]
-- Reinhard Zumkeller, Nov 15 2012
(PARI) is(n)=n>3 && Set(factor(n)[, 2]%2)[1]==0 \\ Charles R Greathouse IV, Oct 16 2015
(Python)
from itertools import count, islice
from sympy import factorint
def A072587_gen(startvalue=1): # generator of terms
return filter(lambda n:not all(map(lambda m:m&1, factorint(n).values())), count(max(startvalue, 1)))
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jun 23 2002
EXTENSIONS
Thanks to Zak Seidov, who noticed that 1 had to be removed. - Reinhard Zumkeller, Nov 15 2012
STATUS
approved