login
This site is supported by donations to The OEIS Foundation.

 

Logo

Annual Appeal: Please make a donation (tax deductible in USA) to keep the OEIS running. Over 5000 articles have referenced us, often saying "we discovered this result with the help of the OEIS".

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified December 5 13:23 EST 2016. Contains 278767 sequences.