OFFSET
1,1
COMMENTS
Minimum number of digits is taken to be 4 as all 3-digit primes would be trivial members.
Zero may occur only as second digit from left. - Zak Seidov, Dec 28 2020
All the digits after the two first digits from left are necessarily odd. - Bernard Schott, Mar 20 2022
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..1000
EXAMPLE
11317 is a term as the three substrings of length 3 i.e. 113,131 and 317 all are primes.
MATHEMATICA
Do[ If[ Union[ PrimeQ[ Map[ FromDigits, Partition[ IntegerDigits[ Prime[n]], 3, 1]]]] == {True}, Print[ Prime[n]]], {n, PrimePi[1000] + 1, 10^3}]
Select[Prime[Range[169, 800]], AllTrue[FromDigits/@Partition[ IntegerDigits[ #], 3, 1], PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Mar 05 2019 *)
PROG
(Haskell)
a069489 n = a069489_list !! (n-1)
a069489_list = filter g $ dropWhile (<= 1000) a000040_list where
g x = x < 100 || a010051 (x `mod` 1000) == 1 && g (x `div` 10)
-- Reinhard Zumkeller, Apr 07 2014
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Amarnath Murthy, Mar 30 2002
EXTENSIONS
Edited, corrected and extended by Robert G. Wilson v, Apr 12 2002
STATUS
approved