OFFSET
1,1
FORMULA
a(n) = PrimePi(A018800(n)). - Michel Marcus, Oct 19 2013
EXAMPLE
a(4)=13 because prime[13]=41 is the smallest prime starting with 4.
CROSSREFS
KEYWORD
easy,base,nonn
AUTHOR
Zak Seidov, Jul 07 2003
STATUS
approved