A199988 Numbers whose product of digits is 6.

6, 16, 23, 32, 61, 116, 123, 132, 161, 213, 231, 312, 321, 611, 1116, 1123, 1132, 1161, 1213, 1231, 1312, 1321, 1611, 2113, 2131, 2311, 3112, 3121, 3211, 6111, 11116, 11123, 11132, 11161, 11213, 11231, 11312, 11321, 11611, 12113, 12131, 12311, 13112, 13121

Offset

1,1

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Maple

f:= proc(d) local b, i, t;
   b:= (10^d-1)/9;
   op(sort([seq(b+5*10^i, i=0..d-1), seq(b+10^t[1]+2*10^t[2], t = combinat:-permute([$0..d-1], 2))]))
end proc:
seq(f(i), i=1..5); # Robert Israel, Jan 13 2021

Mathematica

Select[Range[20000], Times @@ IntegerDigits[#] == 6 &] (* T. D. Noe, Nov 16 2011 *)

Prog

(Python)
from sympy import prod
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: yield int("".join(mp))
print(list(agen(5))) # Michael S. Branicky, Jun 16 2021

Crossrefs

Subsequence of A034053.

Cf. A007954.

Sequence in context: A340497 A051808 A034053 * A114222 A348229 A275641

Adjacent sequences: A199985 A199986 A199987 * A199989 A199990 A199991

Keyword

nonn,look,base

Author

Jaroslav Krizek, Nov 13 2011

Status

approved