OFFSET
1,1
LINKS
Jason Yuen, Table of n, a(n) for n = 1..10000
EXAMPLE
139 is a term as 19 and 3 are both primes.
PROG
(PARI) forprime(p=1, 1440, if(isprime(indigs(p))&&isprime(exdigs(p)), print1(p, ", ")))
(Python)
from sympy import isprime, primerange
for p in primerange(100, 1440):
if isprime(int(str(p)[1:-1])) and isprime(int(str(p)[0]+str(p)[-1])):
print(p) # Jason Yuen, Apr 21 2024
CROSSREFS
KEYWORD
base,nonn,easy
AUTHOR
Amarnath Murthy, Nov 05 2002
EXTENSIONS
Edited and extended by Klaus Brockhaus, Nov 06 2002
STATUS
approved