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%I #11 Jun 16 2021 10:17:39
%S 6,16,32,116,123,132,161,213,231,312,321,611,1116,1132,1161,1312,1611,
%T 3112,3211,6111,11116,11123,11132,11231,11312,11611,12131,12311,13112,
%U 13211,21113,21131,21311,23111,31112,31211,32111,61111,111116,111123,111132,111161
%N Composite numbers whose product of digits is 6.
%H Michael S. Branicky, <a href="/A201055/b201055.txt">Table of n, a(n) for n = 1..10860</a> (all terms with <= 32 digits)
%e Number 123 is in sequence because 1*2*3 = 6.
%o (Python)
%o from sympy import prod, isprime
%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:
%o t = int("".join(mp))
%o if not isprime(t): yield t
%o print(list(agen(6))) # _Michael S. Branicky_, Jun 16 2021
%Y Cf. A199988 (numbers whose product of digits is 6).
%Y Complement of A107692 (primes whose product of digits is 6) with respect to A199988.
%Y Subsequence of A201020 (composite numbers whose multiplicative digital root is 6).
%K nonn,base
%O 1,1
%A _Jaroslav Krizek_, Nov 26 2011
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