A201055 Composite numbers whose product of digits is 6.

6, 16, 32, 116, 123, 132, 161, 213, 231, 312, 321, 611, 1116, 1132, 1161, 1312, 1611, 3112, 3211, 6111, 11116, 11123, 11132, 11231, 11312, 11611, 12131, 12311, 13112, 13211, 21113, 21131, 21311, 23111, 31112, 31211, 32111, 61111, 111116, 111123, 111132, 111161

Offset

1,1

Links

Michael S. Branicky, Table of n, a(n) for n = 1..10860 (all terms with <= 32 digits)

Example

Number 123 is in sequence because 1*2*3 = 6.

Prog

(Python)
from sympy import prod, isprime
from sympy.utilities.iterables import multiset_permutations
def agen(maxdigits):
    for digs in range(1, maxdigits+1):
        for mp in multiset_permutations("1"*(digs-1) + "236", digs):
            if prod(map(int, mp)) == 6:
                t = int("".join(mp))
                if not isprime(t): yield t
print(list(agen(6))) # Michael S. Branicky, Jun 16 2021

Crossrefs

Cf. A199988 (numbers whose product of digits is 6).

Complement of A107692 (primes whose product of digits is 6) with respect to A199988.

Subsequence of A201020 (composite numbers whose multiplicative digital root is 6).

Sequence in context: A061235 A239358 A171494 * A071857 A099399 A338164

Adjacent sequences: A201052 A201053 A201054 * A201056 A201057 A201058

Keyword

nonn,base

Author

Jaroslav Krizek, Nov 26 2011

Status

approved