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A281316
Prime number p such that the decimal representation of its binary reflected Gray code is also a prime.
2
2, 3, 5, 13, 29, 41, 53, 73, 113, 149, 157, 173, 181, 197, 229, 233, 241, 293, 313, 317, 349, 373, 397, 541, 557, 653, 661, 673, 733, 757, 769, 773, 797, 809, 857, 953, 977, 1009, 1033, 1109, 1181, 1193, 1217, 1277, 1289, 1301, 1433, 1549, 1637, 1709, 1733, 1741, 1877, 1993, 2029, 2053, 2081
OFFSET
1,1
COMMENTS
Prime number p such that A003188(p) is in A000040.
LINKS
EXAMPLE
53 is in the sequence because the decimal representation of its binary reflected Gray code is 47 and both 53 and 47 are primes.
PROG
(Python)
from sympy import isprime
def G(n):
....return int(bin(n^(n/2))[2:], 2)
i=1
j=1
while j<=10000:
....if isprime(i)==True and isprime(G(i))==True:
........print str(j)+" "+str(i)
........j+=1
....i+=1
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Indranil Ghosh, Jan 20 2017
STATUS
approved