OFFSET
1,1
LINKS
Indranil Ghosh, Table of n, a(n) for n = 1..481
EXAMPLE
521 is in the sequence because 521_10 = 1100001101_2 and both 521 and 1100001101 are prime numbers in base 10.
PROG
(Python)
from sympy import isprime
def gray(n):
return bin(n^(n//2))[2:]
i=1
j=1
while j<=481:
if isprime(i)==True and isprime(int(gray(i)))==True:
print(str(j)+" "+str(i))
j+=1
i+=1
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Indranil Ghosh, Jan 18 2017
STATUS
approved
