

A244607


Numbers k such that (product of digits of k)  1 is prime.


1



3, 4, 6, 8, 13, 14, 16, 18, 22, 23, 24, 26, 27, 29, 31, 32, 34, 36, 38, 41, 42, 43, 45, 46, 48, 54, 56, 61, 62, 63, 64, 65, 67, 68, 69, 72, 76, 81, 83, 84, 86, 89, 92, 96, 98, 113, 114, 116, 118, 122, 123, 124, 126, 127, 129, 131, 132, 134, 136, 138, 141, 142, 143, 145, 146
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OFFSET

1,1


COMMENTS

This sequence is infinite. With any number a(n), you can add infinitely many 1's to its decimal representation. E.g., 32 is in this sequence, so 321, 312, 3211, 32111, 31121, 11321, etc. are also terms of this sequence.
A number k is a term of this sequence iff A007954(k) is in A008864.


LINKS

Jens Kruse Andersen, Table of n, a(n) for n = 1..10000


EXAMPLE

3*2  1 = 5 is prime. Thus 32 is a term of this sequence.


PROG

(PARI) for(n=1, 10^3, d=digits(n); p=prod(i=1, #d, d[i]); if(isprime(p1), print1(n, ", ")))


CROSSREFS

Cf. A007954, A008864, A089377, A081988.
Sequence in context: A146566 A204658 A139041 * A136483 A240494 A280250
Adjacent sequences: A244604 A244605 A244606 * A244608 A244609 A244610


KEYWORD

nonn,base,easy


AUTHOR

Derek Orr, Jul 01 2014


EXTENSIONS

Wrong term removed by Jens Kruse Andersen, Jul 13 2014


STATUS

approved



