OFFSET
1,1
FORMULA
a(n) equals almost A096509(10^n) >= a(n) because here only primes are counted, the true prime powers not.
EXAMPLE
a(5)=3 and the 3 primes in [99988,100012] are {99989,99991,100003}.
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Jul 14 2004
STATUS
approved