OFFSET
1,1
COMMENTS
There are two primes < 10: 2 and 5.
FORMULA
a(n) = sum(A218209(k), k=1..n)
MATHEMATICA
n = -1; cnt = 0; Do[While[n++; p = 3*n^2 + 2; p < 10^e, If[PrimeQ[p], cnt++]]; n--; cnt, {e, 10}] (* T. D. Noe, Oct 23 2012 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Martin Renner, Oct 23 2012
STATUS
approved