A096838 Number of primes in the neighborhood of prime(n), the n-th prime in the center with radius ceiling(log(prime(n))).

2, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 2, 1, 2, 2, 2, 3, 2, 2, 2, 1, 2, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 2, 3, 4, 4, 3, 1, 3, 4, 4, 4, 3, 2, 2, 3, 3, 3, 3, 4, 3, 3, 1, 3, 4, 4, 3, 2, 2, 3, 3, 4, 2, 2, 3, 3, 3, 2, 2, 2, 1, 2, 2, 2, 3, 3, 3, 2, 3, 4, 4, 3, 1, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 3, 3, 3

Offset: 1

Author

Labos Elemer, Jul 14 2004

Keywords

• nonn

Examples

			a(100)=2 and the two primes in [534,548] are {541,547};
		

Crossrefs

Cf. A096509-A096523, A096830-A096840.

Formula

a(n) almost equals A096509(prime(n)) >= a(n) because here only primes are counted, the true prime powers not.

For all n, a(n) >= 1.