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