OFFSET
1,2
COMMENTS
If p is prime, then p-1 is in the sequence.
Using the prime number theorem in arithmetic progressions k*n+b with gcd(k,b)=1 and its uniformity over k<=exp(c*sqrt(log(x))), one can prove that the counting function of a(n)<=x is equivalent to 2*x/log(x), as x tends to infinity.
PROG
(PARI) isok(n) = my(nextn = n+1); while (hammingweight(bitxor(n, nextn)) != 1, nextn++); isprime(nextn); \\ Michel Marcus, Jul 01 2014
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Vladimir Shevelev, Mar 04 2012
STATUS
approved