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A346657
Numbers that are not divisible by the product of their nonzero digits.
0
13, 14, 16, 17, 18, 19, 21, 22, 23, 25, 26, 27, 28, 29, 31, 32, 33, 34, 35, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 56, 57, 58, 59, 61, 62, 63, 64, 65, 66, 67, 68, 69, 71, 72, 73, 74, 75, 76, 77, 78, 79, 81, 82, 83, 84, 85, 86, 87
OFFSET
1,1
EXAMPLE
The product of the nonzero digits of 42 is 4*2 = 8, which does not divide 42.
MATHEMATICA
Select[Range[100], !Divisible[#, Times @@ Select[IntegerDigits[#], #1 > 0 &]] &] (* Amiram Eldar, Jul 27 2021 *)
PROG
(Python)
from math import prod
def ok(n): return n > 0 and n%prod([int(d) for d in str(n) if d != '0'])
print(list(filter(ok, range(88)))) # Michael S. Branicky, Jul 27 2021
(PARI) isok(k) = k % vecprod(select(x->(x>0), digits(k))); \\ Michel Marcus, Jul 28 2021
CROSSREFS
Complement of A055471.
Sequence in context: A108854 A106007 A048037 * A171492 A054031 A060275
KEYWORD
nonn,easy,base
STATUS
approved