OFFSET
1,2
COMMENTS
Is this sequence infinite? - Charles R Greathouse IV, Sep 07 2012
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
EXAMPLE
77 = 11 * 7 belongs to this sequence but 75 does not as 25 (with a 2) divides 75.
MATHEMATICA
Select[Range[250], And@@OddQ/@Flatten[IntegerDigits/@Divisors[ # ]]&]
PROG
(PARI) f(n)=vecmin(Vec(Vecsmall(Str(n)))%2)
is(n)=fordiv(n, d, if(!f(d), return(0))); 1 \\ Charles R Greathouse IV, Sep 07 2012
(Python)
from itertools import islice, count
from sympy import divisors
def A066640(): return filter(lambda n: all(set(str(m)) <= {'1', '3', '5', '7', '9'} for m in divisors(n, generator=True)), count(1, 2))
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Amarnath Murthy, Dec 28 2001
EXTENSIONS
Corrected and extended by Harvey P. Dale, Jan 01 2002
STATUS
approved