OFFSET
1,3
EXAMPLE
a(3)=15, since there are 15 zeros in primes less than 1000. Namely: 101, 103, 107, 109, 307, 401, 409, 503, 509, 601, 607, 701, 709, 809, 907.
MATHEMATICA
Table[Count[IntegerDigits[Prime[Range[PrimePi[10^n-1]]]], 0, 2], {n, 7}] (* Robert Price, Jun 16 2019 *)
CROSSREFS
KEYWORD
nonn,base,more
AUTHOR
Robert Price, Nov 08 2013
EXTENSIONS
a(14) from Giovanni Resta, Jul 20 2015
STATUS
approved