OFFSET
1,1
COMMENTS
There are exactly eight primes whose digits are primes in strictly increasing order: 2, 3, 5, 7, 23, 37, 257, 2357. - James C. McMahon, Jul 04 2023
There are exactly six primes whose digits are primes in strictly decreasing order: 2, 3, 5, 7, 53, 73. - James C. McMahon, Aug 09 2023
LINKS
Caldwell and Honaker, 2357, Prime Curios!
MATHEMATICA
Select[Range[10000], PrimeQ[ # ] && Length[IntegerDigits[ # ]] == Length[Union[IntegerDigits[ # ]]] && Complement[IntegerDigits[ # ], {2, 3, 5, 7}] == {} &]
PROG
(PARI) is(k) = isprime(k) && setintersect([2, 3, 5, 7], v=vecsort(digits(k))) == v; \\ Jinyuan Wang, Mar 27 2020
CROSSREFS
KEYWORD
nonn,base,fini,full
AUTHOR
Tanya Khovanova, Dec 24 2006
STATUS
approved
