OFFSET
1,1
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
Alejandro J. Becerra Jr., Python code for computing terms of A089971, A089981, A090707-A090710, A235394-A235395.
EXAMPLE
13 is prime in decimal and also when considered as a number in base 4: 13 [base 4] = 7 [base 10] which is also prime.
MATHEMATICA
Select[ FromDigits@# & /@ IntegerDigits[ Prime@ Range@ 270, 4], PrimeQ] (* Robert G. Wilson v, Jan 05 2014 *)
FromDigits[#, 10]&/@Select[Tuples[{0, 1, 2, 3}, 5], AllTrue[{FromDigits[#, 4], FromDigits[#, 10]}, PrimeQ]&] (* Harvey P. Dale, Jul 30 2021 *)
PROG
(PARI) forprime(p=2, 1e4, if(isprime(t=fromdigits(digits(p, 4))), print1(t", "))) \\ Charles R Greathouse IV, Apr 22 2015
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Cino Hilliard, Jan 18 2004
EXTENSIONS
Name, example and offset corrected by M. F. Hasler, Jan 03 2014
STATUS
approved