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A320725 Prime numbers such that all other numbers obtained from all permutations of all subsets of the digits are nonprime. 1
2, 3, 5, 7, 11, 19, 41, 61, 89, 409, 449, 499, 881, 6469 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Sequence is finite since it is a subsequence of a finite sequence (A071062).

This is complete: there are only 14 terms in the sequence.

LINKS

Table of n, a(n) for n=1..14.

EXAMPLE

449 is in this sequence because it's prime and none of the numbers 4, 9, 44, 49, 94, 494 and 944 is prime.

MATHEMATICA

Select[Prime@ Range[10^3], NoneTrue[DeleteCases[FromDigits /@ Rest@ Union@ Apply[Join, Permutations /@ Subsets@ IntegerDigits@ #], #], PrimeQ] &] (* Michael De Vlieger, Oct 22 2018 *)

CROSSREFS

Subsequence of A071062.

Cf. A320726 (the same for composite numbers).

Sequence in context: A089769 A033274 A071062 * A320771 A002231 A087769

Adjacent sequences:  A320722 A320723 A320724 * A320726 A320727 A320728

KEYWORD

nonn,base,fini,full

AUTHOR

Daniel Lignon, Oct 19 2018

STATUS

approved

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Last modified April 18 10:55 EDT 2019. Contains 322209 sequences. (Running on oeis4.)