OFFSET
1,2
EXAMPLE
1 is a term as 751 is prime; 2 isn't, as 752 is composite; 37 is, as 7537 is prime.
PROG
(Sage) is_A107643 = lambda n: is_prime(Integer('75'+str(n))) # D. S. McNeil, Dec 10 2010
(Magma) [ n: n in [1..700] | IsPrime(Seqint(Intseq(n) cat [5, 7])) ]; // Vincenzo Librandi, Feb 02 2011
CROSSREFS
KEYWORD
nonn,base,less
AUTHOR
Parthasarathy Nambi, Jun 09 2005
STATUS
approved