1,3

For large n, the average value of a(n) is about 4. See A138290 for the n such that a(n)=0. - T. D. Noe, Mar 14 2008

T. D. Noe, Table of n, a(n) for n=1..2048

A. Karttunen and J. Moyer, C-program for computing the initial terms of this sequence

Samuel S. Wagstaff, Jr., Prime Numbers with a fixed number of one bits or zero bits in their binary representation, Exp. Math. vol. 10, issue 2 (2001) 267, Table 3. - From N. J. A. Sloane, Jun 19 2011.

Samuel S. Wagstaff, Jr., Prime Numbers with a fixed number of one bits or zero bits in their binary representation, Exp. Math. vol. 10, issue 2 (2001) 267, Table 3.

Index entries for sequences related to occurrences of various subsets of primes in range ]2^n,2^(n+1)]

(PARI) a(n) = sum(k=2^n+1, 2^(n+1), isprime(k) && (#select(x->x==0, binary(k))==1)); \\ Michel Marcus, Sep 11 2015

Cf. A095018.

Sequence in context: A257989 A095201 A272143 * A137345 A060755 A104594

Adjacent sequences: A095055 A095056 A095057 * A095059 A095060 A095061

nonn

Antti Karttunen, Jun 01 2004

approved