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A131648 Primes > 100 in which every multi-digit substring is also prime. 3
113, 131, 137, 173, 179, 197, 311, 313, 317, 373, 379, 419, 431, 479, 613, 617, 619, 673, 719, 797, 971, 1373, 3137, 3797, 6131, 6173, 6197, 9719 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Minimum number of digits is taken to be 3 as all two-digit primes would be trivial members.

LINKS

Table of n, a(n) for n=1..28.

EXAMPLE

9719 is a member becauase 97, 71, 19, 971, 719, 9719 are all primes.

MATHEMATICA

Select[Prime[Range[26, 1300]], And@@PrimeQ[Flatten[Table[FromDigits/@ Partition[ IntegerDigits[#], n, 1], {n, 2, IntegerLength[#]-1}]]]&] (* Harvey P. Dale, Nov 03 2012 *)

CROSSREFS

Cf. This sequence is a subsequence of A069488 - Primes > 100 in which every substring of length 2 is also prime.

Sequence in context: A060591 A214847 A069488 * A180441 A180421 A180407

Adjacent sequences:  A131645 A131646 A131647 * A131649 A131650 A131651

KEYWORD

base,fini,full,nonn

AUTHOR

Tanya Khovanova, Sep 09 2007

STATUS

approved

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Last modified November 21 11:17 EST 2014. Contains 249777 sequences.