A096836 Number of primes in the neighborhood of 10^n with radius ceiling(log(10^n)).

3, 3, 1, 2, 3, 1, 1, 2, 3, 1, 3, 1, 1, 3, 1, 0, 7, 5, 1, 3, 0, 2, 2, 2, 1, 0, 0, 0, 2, 3, 3, 2, 4, 0, 2, 1, 3, 1, 5, 2, 0, 2, 4, 4, 2, 1, 3, 3, 3, 1, 0, 0, 0, 1, 2, 2, 1, 0, 1, 4, 4, 1, 2, 5, 2, 1, 4, 2, 3, 3, 2, 3, 3, 2, 1, 1, 2, 3, 1, 4, 4, 0, 4, 0, 2, 2, 0, 2, 3, 2, 6, 0, 3, 4, 4, 1, 1, 4, 0, 0, 4, 3, 3, 0, 3

Offset: 1

Author

Labos Elemer, Jul 14 2004

Keywords

• nonn

Examples

			a(5)=3 and the 3 primes in [99988,100012] are {99989,99991,100003}.
		

Crossrefs

Cf. A096509-A096523, A096830-A096840.

Formula

a(n) equals almost A096509(10^n) >= a(n) because here only primes are counted, the true prime powers not.