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A199988 Numbers whose product of digits is 6.

%I A199988 #23 Jun 16 2021 10:16:53
%S A199988 6,16,23,32,61,116,123,132,161,213,231,312,321,611,1116,1123,1132,
%T A199988 1161,1213,1231,1312,1321,1611,2113,2131,2311,3112,3121,3211,6111,
%U A199988 11116,11123,11132,11161,11213,11231,11312,11321,11611,12113,12131,12311,13112,13121
%N A199988 Numbers whose product of digits is 6.
%H A199988 Robert Israel, <a href="/A199988/b199988.txt">Table of n, a(n) for n = 1..10000</a>
%p A199988 f:= proc(d) local b,i,t;
%p A199988    b:= (10^d-1)/9;
%p A199988    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))]))
%p A199988 end proc:
%p A199988 seq(f(i),i=1..5); # _Robert Israel_, Jan 13 2021
%t A199988 Select[Range[20000], Times @@ IntegerDigits[#] == 6 &] (* _T. D. Noe_, Nov 16 2011 *)
%o A199988 (Python)
%o A199988 from sympy import prod
%o A199988 from sympy.utilities.iterables import multiset_permutations
%o A199988 def agen(maxdigits):
%o A199988     for digs in range(1, maxdigits+1):
%o A199988         for mp in multiset_permutations("1"*(digs-1) + "236", digs):
%o A199988             if prod(map(int, mp)) == 6: yield int("".join(mp))
%o A199988 print(list(agen(5))) # _Michael S. Branicky_, Jun 16 2021
%Y A199988 Subsequence of A034053.
%Y A199988 Cf. A007954.
%K A199988 nonn,look,base
%O A199988 1,1
%A A199988 _Jaroslav Krizek_, Nov 13 2011