A281316 Prime number p such that the decimal representation of its binary reflected Gray code is also a prime.

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

Indranil Ghosh, Table of n, a(n) for n = 1..10000

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

Cf. A000040, A003188, A281227.

Sequence in context: A089477 A099962 A173718 * A329241 A177502 A072536

Adjacent sequences: A281313 A281314 A281315 * A281317 A281318 A281319

Keyword

nonn,base

Author

Indranil Ghosh, Jan 20 2017

Status

approved