A107692 - OEIS

A107692

Primes whose product of digits is 6.

23, 61, 1123, 1213, 1231, 1321, 2113, 2131, 2311, 3121, 11161, 11213, 11321, 12113, 13121, 16111, 31121, 111611, 611111, 1111213, 1112113, 1112131, 1131121, 1211311, 2111311, 3112111, 11111161, 11112113, 11211131, 11231111, 11312111

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OFFSET

1,1

LINKS

Michael S. Branicky, Table of n, a(n) for n = 1..10199 (all terms with <= 136 digits; terms 1..1000 from Harvey P. Dale)

MATHEMATICA

Union[ Flatten[ Table[ Select[ Sort[ FromDigits /@ Join[ Permutations[ Flatten[{6, Table[1, {n}]}]], Permutations[ Flatten[{2, 3, Table[ 1, {n - 1}]}] ]]], PrimeQ[ # ] &], {n, 0, 7}]]]

Select[Prime[Range[750000]], Times@@IntegerDigits[#]==6&] (* Harvey P. Dale, May 29 2016 *)

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 isprime(t): yield t

print(list(agen(8))) # Michael S. Branicky, Jun 16 2021